The Competitiveness of Nations in a Global Knowledge-Based Economy
Marjorie
Grene
Aristotle
and Modern Biology
Journal of the History of Ideas, 33 (3)
July-Sept. 1972, 395-424.
Content
1. Aristotelianism
& Modern Science
4. Teleology, Necessity &
Tautology
HHC: titling added |
1. Aristotelianism
& Modern Science
Science had its origin, if not in opposition to
Aristotle, at least in opposition to Aristotelianism.
But science in its most authoritative
form was what came to be called physics, not biology. Faced with the recent crisis in biology, in
which the life sciences have been threatened with reduction to microversions of themselves and ultimately to chemistry and
physics, one wonders if the besieged biologists, or at any rate their
philosophical defenders, might not after all learn something to their advantage
by reflecting on the one great philosopher who was also a great biologist. And we can learn from Aristotle; not,
however, in a simple or straightforward fashion. There is no use just contrasting, as some have
been tempted to do, Democritean with Aristotelian
science and putting physicists in the former class, biologists in the latter. Even if we reject Simpson’s alleged
reaffirmation of Roger Bacon and stoutly deny that “the study of Aristotle
increases ignorance,” [1] we must
nevertheless admit that in some important respects biology, like all modern
science, really is, and must be, un-Aristotelian. This thesis could be defended in a number of
ways; let me select four. [2]
First, the role of abstraction and the relation of
scientific reasoning to everyday experience differ deeply in Aristotelian and
in modern science. Only mathematics,
Aristotle insists, abstracts from most of the ordinary perceptible
properties (qualities, relations, states) of the things around us. Natural science, as he understands it, remains
within the framework of everyday perception and makes more precise,
within that framework, our formulation and understanding of the essential
natures of quite ordinarily accessible entities. Modern science began and continues, on the
contrary, precisely by closing its eyes to all but a few highly selected
features of the world around us, abstracting from all but those variables which
give promise of susceptibility to
1. G. G. Simpson, Principles
of Animal Taxonomy (New York and London, 1961), 36n:
“I tend to agree with Roger Bacon that the study of Aristotle increases
ignorance.” In fact Bacon was objecting
to the current translations of Aristotle, not to Aristotle’s teachings
themselves. His statement reads as
follows: “Si enim haberem potestatem super libros Aristotelis ego facerem omnes cremari
qui non est nisi temporis amissio studere in illis et causa erroris et multiplicatio ignorantiae ultra id quod valeat explicari. Et quoniam
labores Aristotelis sunt fundamenta totius sapientiae, ideo nemo potest
aestimare quantum dispendium
accidit Latinis quia malas translationes
receperunt philosophi.”
(“Compendium Studii Philosophiae,”
Bacon Opera Inedita, Rolls Series number 15,
469). I am grateful to my
colleague, Professor John Malcolm, for finding this passage.
2. See my Portrait of Aristotle
(Chicago and London, 1964), esp. Ch. VII.
395
some sophisticated, usually quantitative,
manipulation by the experimenter or the theorist.
Secondly, because he sticks so closely to the
concrete, limited, and limiting physiognomy of things encountered in the
everyday world, the Aristotelian scientist never confronts the teasing problem
of induction which the modern scientist, or better, philosopher of science,
necessarily has to face. The possible
data of scientific calculations are infinite, the calculations themselves and
their results are finite. However
ingenious the arguments that have been used to comfort us before this gap, the
gap remains. For
Aristotle it does not exist. Admittedly
even the most ingenious experimenter must rely, in Aristotelian fashion, on the
stability of his surroundings: on his materials, his apparatus, as being
reliably not simply this-here, but this-such. [3] Every time you pick up a
handful of CuSO4 crystals, Norman Campbell argued, you are in effect
acknowledging a law of nature: you confidently expect these blue
crystals to have the same chemical properties as they did yesterday and will
tomorrow. [4] Confidence
in such stabilities does indeed depend, if you like, on Aristotelian induction,
where we move from a rough and ready perception of the character of a thing to
a more precise knowledge of just what kind of thing it is. But - pace Hume - it is only after this
everyday induction that the problem of induction in science first begins: that
is, the problem evoked by the necessary disproportion between data and
hypothesis, between evidence and conclusion. Just because it remains within the horizon of
everyday things-to-hand, Aristotelian science evades altogether the problem of
induction in this its modern form.
A third way to emphasize the same contrast is to
stress the role of productive imagination in scientific discovery. Aristotelian phantasia
is powerless to excel what Kant called reproductive imagination. The productive power of that faculty, not a
priori and once-for-all, as in the Schematism of
the Critique of Pure Reason, but advancing hazardously to and beyond
ever new frontiers: that is the moving force behind the scientific adventure, a
force wholly beyond the ken of the much cosier Prinzipienforschung of Aristotle, cradled as
it is within the comforting embrace of the familiar everyday world.
3. Wolfgang Wieland (Die Aristotelische Physik [Göttingen, 1962],
95n.) argues that the fashion in which modern physicists take a given
experiment as general is still Aristotelian: “[HHC: German not
reproduced]” It
is, in his view, modern theories of induction that mislead us here. But those theories have recognized a
logical gap which Aristotle failed, and for his purposes did not need, to
recognize.
4. Norman Campbell, What is
Science? (New York and London, 1952, 1921), Ch.
II.
396
All this concerns Aristotelian methodology. Cosmologically, too, and especially for
biology, there are features of Aristotelian science which the modern mind
radically rejects. Aristotle’s world is
finite, unique, eternal, consisting of a finite number of eternally existent
species, “endeavoring” in their re-production to simulate the eternal circling
of the celestial spheres (so he argues at the close of the
De Generatione et Corruptione
[5]). For modern biology, this eternal frame is
shattered. All things flow. For many modern biologists, indeed, the
theory of evolution is comprehensive for their science; all biological
research, they feel, somehow derives from and
contributes to it. That claim may be
exaggerated. But even research seemingly
unconnected with evolution is nevertheless related to it in some degree, as
figure to ground. Some of Aristotle’s
detailed biological work too was sound and still retains its validity despite
the incorrectness of his cosmological theory, e.g., his description of chick
development or his account of the life history of Parasilurus
aristotelis or of Mustelus
laevus. Much
modern research, similarly, may reach correct conclusions independently of the
general conception of life’s development from the non-living or of the
transmutation of species. Yet the overall
thrust of modern biology has been radically altered by the idea of evolution,
much as the Aristotelian science of nature was guided by the contrary view of a
static and finite cosmos. In their
overall implications, the two are incompatible.
Despite these contrarieties, however, there is much to
be learned from Aristotle in relation to the philosophical problems of biology.
I want to discuss in this context three
Aristotelian concepts: [HHC: Greek not reproduced] telos
or the [HHC: Greek not reproduced], that for the sake of which; [HHC:
Greek not reproduced] in contrast both to [HHC: Greek not reproduced… ], eidos as form and eidos as species, and finally that most
puzzling of Aristotelian phrases, [HHC: Greek not reproduced], the
“being-what-it-is” of each kind of thing.
First, telos.
Again, it was Aristotelian teleology
that seventeenth-century innovators were most emphatically determined to abolish
from the study of nature. And again, as
Aristotelian teleology had come to be understood, or misunderstood, this was a
necessary move. Yet some sort of
teleology, or teleonomy, as some modern biologists
prefer to call it, keeps creeping back into biological language and thought. Let us consider, then, how and where something
like Aristotle’s telos occurs in modern
biology and how modern usage compares with his.
Two misconceptions must first be set aside. 1) Telos is
not in the first instance - and in the study of nature is not at all – “purpose
or plan.” In nature, “that for the sake
of which” a series of events takes place is the intrinsic endpoint in which, if
nothing fatally interferes,
5. Degeneratione
et corruptione, II, 11,
338b7ff.
397
that series normally culminates. What usually happens to a fertilized robins’
egg, for instance? A baby robin hatches
out of it; that is its telos. There is absolutely no question of any
kind of “purpose” here, either man’s or God’s. To suppose otherwise is to introduce a Judaeo-Christian confusion of which Aristotle must be
entirely acquitted. 2) Nor is Aristotle
interested primarily in one over-all cosmic telos.
Despite the passage from De Generatione e.t Corruptione already referred to, and despite the
“teleological” causality of the unmoved mover, the kind of “ends” that usually
interest Aristotle are the determinate end-points of particular processes
within the natural world. True, the
stability of the universe is, for him, a necessary condition of the orderly
processes of its components; but this is by no means the target of his primary
interest. On the contrary, it was,
again, the Judaeo-Christian God who (with the help of
neo-Platonism) imposed the dominance of a cosmic teleology upon Aristotelian
nature. Such sweeping purpose is the
very contrary of Aristotelian. [6]
The concept of telos
in exactly Aristotle’s sense, however, does occur in exactly the area where
he himself invokes it: in the study of ontogenesis. Here, indeed, the contrast of Aristotelian and
Democritean science still appears valid, at least to
a first approximation. The embryologist
must put questions to the living embryo, in terms to which, and in which, it
can respond. [7] And
this is impossible on principle in terms of a thoroughgoing atomism, since in
those terms there is nothing alive. What might happen to a really Democritean scientist faced with a biological problem was
suggested by Frank Baker in a paper I have quoted elsewhere. Imagine, he says, an observer looking in the
field of a microscope at the filaments of a fungus. “He witnesses,” says Baker,
“that at the tips of the filaments are
disposed a number of radiating branches more frequently segmented than those of
the stalk to which they are attached; which adjointed
elliptical segments are easily set free by pressure in the surrounding medium. But, supposing that he decides to investigate these
segments, what kind of ideas are going to control his choice of further observations;
how will he proceed, loosely speaking, to discover ‘the nature’ of these
structures; and, in brief, in such a context, what does his notion of ‘investigation’
already imply?” [8]
6. See the exposition of Wieland in the work referred to, note 3, above; see also
his Science and Philosophy in Aristotle’s Biology (Darmstadt, 1972). For a close study of Aristotle’s use of telos in the explanation of generation, as
well as, and in relation to, eidos and hyle, see the excellent paper by Anthony Preus, “Science and Philosophy in Aristotle’s Generation of
Animals,” J. Hist. Biol. 3 (1970), 1-52.
7. Cf. M. Grene,
The Knower and the Known (New York and London, 1966), 237.
8. Quoted ibid.,
235-36, from A. E. Baker, “Purpose and Natural Selection: A Defense of
Teleology,” Scientific Journal of the Royal Coil, of Science, 4 (1934),
106-19, 107-08.
398
An old-fashioned chemist, Baker suggests, might throw
these segments (which, unknown to him, we may call spores) into concentrated
H2S04. He would learn something; but
would this “lay an effective basis to the study of
mycology?” And why are these not as good
facts to start with as any other? But
suppose our investigator places the segments on jam (where he first found them)
or sugar, and in the warmth, and watches what happens. He may then discover “their relation to the
life cycle of the fungus.” Actually,
Baker remarks, it would take a whole series of investigators “animated by a
single scientific impulse or tradition” to lay the foundation which would so
much as show him where to start. When he
gets this far he can then, but not before, undertake
his chemical analysis. Only, in other
words, when the concept of germination is understood and its designatum assumed to exist, do the details “fall into
order and acquire a significance,” such that detailed
analysis of some parts of the process of germination can be undertaken. The orderly development of the organism under
investigation must have been assumed, Baker concludes, before the right “facts”
could be selected for further investigation and analysis. [9] An orderly development
toward a normal end, therefore, is necessarily presupposed by the biological
investigator before he can set out to make his investigation. A concept of “that for the sake of which” the
development is occurring, of its natural telos,
is contained in the very question asked.
Such considerations place teleological (or teleonomic) thinking in the position of at least a regulative
idea (in the Kantian sense) at the beginning of biological research. From this point of view telos
is a signpost to the study of nature: a “reflective concept” (em Reflexions-begriff) as Wieland argues. [10] Looking at the endpoint
of the series helps us to start looking for its necessary antecedents; there is
nothing “unscientific” about this, not even anything very un-Democritean. But is
that all there is to it? A Kantian
regulative idea - say, the infinite divisibility of matter, or indeed natural
teleology as Kant coneived it - is a pure as-if. And many modern thinkers would be content
with this, with “the appearance of end,” as Waddington calls it. [11] It’s a makeshift, they
say, a crutch to lean on until we have mastered the necessary and sufficient
conditions, or until we have constructed a machine to simulate an animal, or
until we have synthesized life. Then we
can throw away the crutch and walk alone. [12] Or perhaps, as Piaget
argues, the very idea of a final cause, even in this seemingly harmless form,
is based on a logical error and we don’t need it at all.
9. Baker, op. cit., 108-10.
10. W. Wieland,
op. cit., 254-77.
11. C. H. Waddington, The Strategy of the Genes (London, 1957), 190.
12. See the (by now classic)
interpretation of organicism in Ernest Nagel, The
Structure of Science (New York, 1961), 428-46.
399
It rests, he maintains, on a confusion of three different notions:
physical or physiological causality (cause a produces effect b),
logical implication (the use of A implies the consequence B),
and instrumentality (to get B “we must” use A). [13]
Both these views are mistaken. To assert that a robin’s egg
hatches out a robin and not an oak tree is to state not a regulative idea but a
fact of nature. Nor, a
fortiori, does such an assertion represent any logical howler. At the least, it locates in the real world an
orderly process, the details of which the biologist may undertake to study. It selects a certain segment of orderly
temporal process in its orderliness as the locus of an inquiry. To this extent at least it locates real, not
apparent, ends and suggests really, not seemingly or misguidedly, teleological
questions.
But is that all? If there are real processes with natural
endpoints, real telos in nature, are
there not also teleological answers to the questions we put to nature? This seems to me a much more difficult problem.
Professor C. P. Raven of Utrecht has
written of the application of information theory to biology as “the
formalization of finality,” and I had formerly taken him at his word. [14] Yet now I wonder. What is “finalistic” about information theory?
Admittedly, both teleological
explanation and cybernetical explanation are
complementary to classical causal explanation; in this sense, both resist a
one-level, Democritean approach. But that does not make them equivalent. I prefer to leave this question open here, and
postpone a consideration of multilevelled explanation
in general until I come to the concept of eidos.
For the moment we may take it that
in the study of individual development, the concept of a normal endpoint of
development helps methodologically to locate the place of the inquiry and to
locate it really in nature, whether or no the concept of telos
is also embedded in the solution to the embryologist’s problem.
The most vexing problem with respect to Aristotelian telos and modern biology, however, concerns
not ontogeny, but phylogeny. Granted,
there is a definite, if perhaps limited, role for teleology (or teleonomy) in the study of ontogenesis; can one transfer
the concept of
13. Jean Piaget, Biologie et connaissance (Paris, 1967), 225-26. Piaget refers here to an argument by J.-B. Grize: “HHC: French not reproduced]
14. The Knower and The
Known, Ch. IX, 238.
400
end to the study of evolution, or can one at
least discover in evolutionary explanation an analogue of teleonomic
thinking? It has repeatedly been claimed
both that Darwinian evolutionary theory rejects any cosmic telos
and that it retains the concept of telos
in some more acceptably “scientific” sense. Indeed, it has even been argued that it is
precisely by virtue of its teleological structure that evolutionary theory, and
only evolutionary theory, rescues biology from reduction to physics and makes
it “an autonomous science.” [15] These
claims may perhaps be clarified if we compare the “teleonomic”
thinking of modern evolutionists with Aristotelian teleology.
The fixed endpoint of a natural process, for Aristotle, is the mature form of the adult individual (strictly, of the adult male!) of the species in question. “Nature is like a runner,” he says, “running her course from non-being to being and back again. [16] The being in the case is the developed adult of such and such a kind. In modern evolutionary biology, however, there is no such fixed form; the eidos itself, which is the telos of individual development, is transitory. What remains? For Darwinism, the telos that remains when the eternal species is removed is simply survival. Survival of what? The individual perishes; what survives? In Darwinian terms: the descendants of the slightly more “successful” members of a species. In neo-Darwinian terms: the alleles which made possible the development of phenotypes carrying the slightly more “successful” characters, or rather, statistically, a higher ratio of those alleles in the gene pool of the next generation. A robin’s egg is not, it seems, the way to make a robin, but a robin is a robin’s egg’s way to make more, and more probably surviving, robin’s eggs. The locus of the goal of biological process is not, as it appeared to Aristotle, in the mature individual, who is, as such, mortal and of no concern to evolution, but in the future gene pool of the population of individuals of a potentially interbreeding population.
Take, e.g., Kettlewell’s classic study of industrial melanism. [17] If tree trunks are blackened by industry, birds take more peppered moths, and hence more genes for peppered wings, than they do the carbonaria mutant of the species. Hence, fewer mutant genes are eaten and proportionally more survive. The telos of this process is the greater ratio of carbonaria genes in the next generation. Evolution-
15. F. Ayala, “Biology as an
Autonomous Science,” Amer. Scientist, 56 (1968), 207-21.
16. DeGen.
Anim.741b21ff.
17. H. B. D. Kettlewell, “Selection experiments on industrial melanism in the lepidoptera,” Heredity
9 (1955), 323ff. “A résumé of investigations on the evolution of melanism in the Lepidoptera,” Proc. Roy. Soc. Lond. B.,
145
(1956), 297 ff.
401
arily speaking, that is what the whole
business of being a moth is for; not, indeed, just “for” the survival of
this gene, but if we had a complete count of all the genes in the
population at time t0
and time t1,
the
differential ratio would give us the “end” of the story; the differential
survival of some genes rather than others. But which genes? Whichever ones survive, of
course. If we clean up industry
and the tree trunks bleach again, more peppered and fewer carbonaria
genes survive, and the endpoint goes the other way. Similarly in peacetime healthy human males
are, other things being equal, better adapted - and that means of course in
evolutionary terms more likely to leave descendants - than sickly ones, but in
war time the contrary holds: the halt, the lame, and the blind are better
adapted than the healthy. Biological
process is first and last and always evolution; evolution is first and last and
always a chronicle of survival, the survival of whatever survives.
A strange telos: we
are told simply, what survives survives. But this, it has repeatedly been objected,
looks like a mere tautology. And at
first sight, at least, it has also been repeatedly objected, a tautology seems
to have no explanatory power, let alone the explanatory power that would be
characteristic of a teleological account. For a teleological account distinguishes, and
sets out as aimed at, a goal to which it can then relate the antecedent steps. Here, however, goal and steps are collapsed
into an empty identity.
Yet that identity, we are told, presides over a rich
and precise elaboration of “evolutionary mechanisms,” and hence of teleonomic patterns of structure or behavior. The case for this view is argued in a
thought-provoking book by George Williams, Adaptation and Natural Selection.
Although he accepts, and celebrates,
the tautological character of the principle of natural selection, as the
survival of the fitter in the sense of the more probable survival of what will
more probably survive, he insists nevertheless that
this principle, correctly used, can preside over a vast range of teleonomic investigations:
A frequently helpful, but not
infallible rule is to recognize adaptation in organic systems that show a clear
analogy with human implements. There are
convincing analogies between bird wings and airship wings, between bridge
suspensions and skeletal suspensions, between the vascularization
of a leaf and the water supply of a city. In all such examples, conscious human goals
have an analogy in the biological goal of survival, and similar problems
are often resolved by similar mechanisms. Such analogies may forcefully occur to a
physiologist at the beginning of an investigation of a structure or process and
provide a continuing source of fruitful hypotheses. At other times the purpose of a mechanism may
not be apparent initially, and the search for the goal becomes a motivation for
further study. Adaptation is assumed in
such cases, not on the basis of a demonstrable appropriateness of the means to
the end, but on the direct evidence of complexity and constancy. [18]
18. George Williams, Adaptation
and Natural Selection (Princeton, 1966), 10.
402
The study of the lateral line of fishes, he suggests, is a good example
of this kind of reasoning:
The lateral line is a good
illustration. This organ is a
conspicuous morphological feature of the great majority of fishes. It shows a structural constancy within taxa and a high degree of histological complexity. In all these features it is analogous to
clearly adaptive and demonstrably important structures. The only missing feature, to those who first
concerned themselves with this organ, was a convincing story as to how it might
make an efficient contribution to survival. Eventually painstaking morphological and
physiological studies by many workers demonstrated that the lateral line is a
sense organ related in basic mechanism to audition (Dijkgraaf,
1952, 1963). The fact that man does not
have this sense organ himself, and had not perfected artificial receptors in
any way analogous, was a handicap in the attempt to understand the organ. Its constancy and complexity, however, and the
consequent conviction that it must be useful in some way, were incentives and
guides in the studies that eventually elucidated the workings of an important
sensory mechanism. [19]
How does this kind of teleonomic
thinking compare with the use of telos in
Aristotle? Aristotle presents his
concept of “that for the sake of which” as a guide to the study of nature in
opposition to the thinking of Empedocles, who would elicit the phenomena of the
living world, without ordered ends, out of a combination of chance and
necessity. At one stage in cosmic
history, Empedocles imagines, there were heads and trunks and limbs rolling
about the world. Those that happened to
come together in a viable combination survived; the others perished. This was a very crude theory of natural selection,
to be sure, but a theory of natural selection, nevertheless. Aristotle as a practising
biologist objected: ox-headed man progeny and vine-bearing olives, such as
Empedocles envisages in his transitory world, are an absurdity. What we always have in nature is the
ordered passage to a definite endpoint: man to man, cattle to cattle, grape to
grape, olive to olive. Only where there
are such functioning, ordered series does the study of life begin. Williams would agree. Where we can use only the concepts of chance
and necessity, he insists, we should. Thus
the descent of flying fishes can be explained in terms of physics alone; their
flight, however, which is “contrived,” in analogy to human contrivance, needs,
he argues, another and teleonomic principle of
explanation, as any piece of machinery does.
So, as we saw with the case of ontogenesis, we need,
it seems, a teleological approach to locate a biological problem. But is the explanation, in the case of
selection theory, teleological as well? Have we even found, as in individual
development, a directed process to describe - however we may eventually explain
it? I think not; for explanation in
terms of orthodox evolutionary theory collapses pretty
19. Ibid., 10-11.
403
quickly into pure Empedoclean
chance-times-necessity. Had fishes not
had the sensory mechanism of the lateral line they would not have “heard” their
predators coming and would not have survived. Or better: those whose “hearing” was slightly
more acute left descendents in the gene pool, those not so gifted left fewer
and finally none. Chance mutations
necessarily sorted out by the compulsions of environmental circumstances: that
is a pure Empedoclean, anti-teleological process. The peppered moth case is a striking example. We have here, we are told, “evolution at
work”: now we see the whole process in little. Extrapolate this “mechanism” to the whole
story of life and you have the vast panorama before you: no other principles
are needed. But what is this story? The environment, for extraneous reasons (in
this case the industrial revolution) changes; the gene pool is always changing;
the changed environment necessitates changed predation (birds can’t as easily
see black moths on black trees as peppered ones); changed predation
necessitates differential survival of some genes rather than their alleles. So we necessarily get more black moths
than peppered ones. Extrapolate this
process to the whole of evolution and you see a vast sequence of necessities. True, the sequence is triggered, and kept
going, by a set of curious chances. These, however, are “chances” only in the
sense of being at a tangent to the “normal” sequence of development. They are to be explicated, on principle, in
terms of natural, that is, physico-chemical laws. Thus, given the nature of bituminous coal, the
tree trunks had to be blackened. Given
the chemical nature of DNA, one supposes, the “errors” which occur in its
replication will ultimately be explained also in physico-chemical
terms. They happen by “chance” - just as
in Aristotelian chance - only in the sense that they are outside the usual
sequence of events to which one has been attending, in this case the “normal”
development of the peppered moth. But
they have, or will have, their physico-chemical
explanation, which must ultimately exhibit their necessary occurrence. Again, extrapolate this reduction to the whole
history of nature. Where is the
teleology? It has served as a heuristic
maxim to start us off on our inquiry, but in the sequence of survivals it does
not survive even as a factor in the phenomena described, let alone as an
explanatory principle.
Is there any other way to introduce teleology into
evolution? Many philosophers and some
biologists have tried to do this in terms of a theory of “emergence.” [20] But these theories,
compared either with
20. Among biologists critical
of the neo-Darwinian synthesis, see for example E. S. Russell, The diversity
of animals, Acta Biotheor. 13
(Suppl. 1), 1962, 1-151, Cf. A. Vandel, L’Homme et L’Evolution (Paris, 1949). Among recent philosophers, see M. Polanyi, Personal
Knowledge (Chicago and London, 1958 [Torchbook
edition: New York, 1962], Ch. 13.
404
the precise and limited teleology of Aristotle
or with the vanishing teleology of Darwinism, are vague, and empty of
explanatory power. If one says, for
example, with Vandel (following Bergson)
that life has moved toward an increase of “le psychisme,”
with two high points, the insects (generic inventiveness) and man (individual
inventiveness), two objections at once arise. [21] First, some of the diverse
branches of evolution have gone that way, but not by any means all. What of parasitism, what of long stable forms
like Lingula, what of the vast variety of birds or
“lower” mammals, what of the evolution of plants, etc., etc.? Second, even if we can see, very generally,
some such tendency in the history of life on earth, how did it happen? What does such an assertion of the “emergence”
of psychic powers explain, and how? This
appears an even stranger extrapolation than the Darwinian. For one can imagine the melanism story stretched back to the beginning of time. I suspect (indeed, I have argued elsewhere)
that this extrapolation entails untenable pseudo-reductions of richer to poorer
concepts; but still one can see how it’s done. The “emergence” extrapolation, however, I for
one simply cannot follow at all. There
is a goal, mind or thought or inventiveness, we are told, for which
evolution happened. It is the
achievement of this goal that we are studying when we look at evolution’s
course. But whose goal?
Whose achievement? The giraffe, we know contra Lamarck,
didn’t get a longer neck by trying; and are we to believe that the
brachiopods tried to achieve thought and left it to us to succeed, or tried to
achieve social rituals and left it to the ants to carry them through? Achievements must be some one’s achievements.
A goal, even if it is an Aristotelian telos, not a conscious purpose, must be the
endpoint of some entity’s becoming. Whose achievement is evolution? Whose goal, on an evolutionary scale, is
thought? In any terms available to this
writer at least the very question is nonsense. The concept of telos
is intelligible and useful, I submit, only with reference to something
already in existence. In the study of
evolution, on the contrary, where we have no fixed individuals and therefore no
fixed endpoint of process, we have, whether in the Darwinian view or in the
efforts of “emergence” theorists to revise it, only the appearance of
teleology, not its flesh and blood.
4. Teleology, Necessity
& Tautology
Still, that appearance keeps reappearing. Why? In
emergence theory it is a case of metaphysical aspirations as yet unfulfilled. All honor to them; it may well be that this
controversy will only come to rest once one has accepted a cosmology of some Whiteheadian kind. This,
to most of us, has not yet happened, certainly not in such a fashion as to
affect the practice or the thinking of biologists. But why does neo-Darwinism, as distinct from
those broader and vaguer views, recurrently lay claim
to being teleonomic in its structure?
21. A. Vandel,
op. cii.
405
The answer is not far to seek. To give it will permit one more comparison
with the teleology of Aristotelian science.
Darwinian evolutionary theory appears teleological
because it is first and last a theory of adaptation. Deriving from Paley,
it views all organisms as adaptation machines, aggregates of devices for the
adjustment of the organism to its environment. On this view it is, as Williams insists,
thinking in terms of adaptation, and this alone, that distinguishes biology as
a science from physics and chemistry. Yet
adaptation in evolutionary terms is for survival and survival only. Everything non-trivial in specifically
biological processes reduces to this one phenomenon. But explanation in these terms, as we have
already seen, either collapses into tautology or is reduced to necessity, and
so in either case fails to retain its alleged teleonomic
structure.
How does this situation compare with that of
Aristotelian teleology? First, in
Aristotle we find for each kind of thing a given normal endpoint of
development, and relate to it a set of what Aristotle calls “hypothetical
necessities.” Given, for instance, that
a creature needs to hear - or be somehow sensitive to environmental vibrations
- it will develop some kind of auditory organ, whether a vertebrate ear
or a piscine lateral line. In the modern
version, however, such hypothetical necessities become simple necessities. Since the endpoint to which one might refer
them as means is not fixed in advance, it becomes simply the ineluctable issue
of the preceding steps. Instead,
therefore, of the necessary conditions being relative to the end, the end is
the automatic product of its necessary (and sufficient) conditions. In Aristotle, secondly, the end being given,
its achievement happens “always or for the most part” - but it may fail. All along the way, there is room for
abnormality, for chance. In modern
theory, however, there is no such leeway. Even though, in terms of our present knowledge,
most mutations may be “chance” occurrences, that is so
only in a sense analogous to Aristotelian tyche;
that is, they are caused by some cause and effect sequence outside the
usual pattern of development in the given case. But they are not - or cannot survive - as to
automaton in Aristotle’s sense, as sheer random happenings. Did they not prove to be adaptive as the
environment changes, natural selection would eliminate them. And if they do prove adaptive, on the other
hand, they have to survive. Depending on
how you look at it, in other words, everything is teleological (adaptive) or
everything is necessary. There is no
middle ground for the merely contingent in the interstices of an otherwise
orderly sequence.
It is just this two-edged comprehensiveness, finally,
combined with the authority of an algebraic formulation, that
lends to modern natural selection theory its great explanatory power. First, there is a formal, mathematical
instrument, the algebra of Fisher or Haldane, which
may be used to measure natural selection and which lends
406
weight and precision to experimental results
in this field. Such a formula,
intrinsically tautological, is used to measure changing adaptive relations and
therefore serves the appearance of teleology. But these relations in turn, when viewed as a
series of organism-environment interactions, appear thoroughly necessitated,
not teleological at all. When, however,
such interactions are summed up, for long periods, in algebraic formulation,
the results, neatly ordered, present apparent trends and thus once more give
the appearance of teleology, an appearance once more reduced to necessity when
we visualize the whole sequence of action/reaction from which they have
eventuated. Thus if one accuses
Darwinians of being “mechanistic” they point to the “trends” in evolution as
they see it; if one accuses them of being “teleological” in their thinking,
they point to the necessity of the whole show in terms of environmental
pressure and the consequent changes in gene ratios. And if we try to bring this to-and-fro to
rest, what have we? Once more,
tautology: well, after all, what survives survives. If you look at the process a tergo it appears teleological; if a fronte, necessitated.
And sub specie aeternitatis,
when the theory is summed up in a formula for measuring differential gene
ratios, you have a theorem universally applicable because empty, totally comprehensive
because it expresses a simple identity. [22]
Why do we keep going round this merry-go-round? “Adaptation” is a means-end concept. Yet if all adaptations are for no specifiable
end except survival, one keeps falling back into a universal necessity which is
in turn reducible to the same old tautology. Stretch it out: it’s
teleology. Collapse it one level: it’s necessity. Collapse
it still further: it’s tautology. What is lacking to stabilize this endless
vacillation? This brings me at last to
my second major Aristotelian concept: eidos.
For what is lacking in the modern
concept of adaptation is precisely the definite telos,
which in Aristotle is the mature form of the species, of the type, the [HHC:
Greek not reproduced] of the [HHC: Greek not reproduced].
Nor, of course, do I mean by this some cosmic goal. Again, there are no such goals within
Aristotelian biology. True, there are
such in Aristotelian cosmology, as e.g. in respect to the proof of the unmoved
mover. In the framework of biological
investigation, however, we need not, indeed we may not, invoke such dialectical
arguments. Modern biology, however,
lacks even the more limited and concrete end-points of Aristotelian science. In short, when Darwinism evicted the
watchmaker of Paley’s famous watch, it threw out as
well the telos of the watch itself. But without a terminus ad quem of development, without a terminus ad quem for our understanding of the organization of a
living system, of an organism, of an organ, of an organ-
22. Cf. my analysis of R. A.
Fisher’s Genetical Theoretical Theory of
Natural Selection, in The Knower and the Known, 253-66.
407
elle, one has no
univocal concept of adaptation, of the adjustment of these means to that end. True, the organism, the organ, the organelle
is continuously adapting itself to its environment, both internal and external;
but what for? To what end? In ontogenesis, to the end of maturation and
self-maintenance of the organism, the organ or the, organelle, that is, to the
end of the origination and conservation of some form. The processes of adaptation, as distinct
from their result and adaptedness, are thus related
as dynamic processes to their goal, that is, to the actuality of the organized
system which comes into being or maintains itself in being through those
processes. And the result, adaptedness, as differentiated being-such-and-such of the
parts of the organism, the organ or the organelle, is also subordinated,
therefore, to the development or maintenance of the form, the eidos, of the whole. It is, then, precisely the Aristotelian
concept of form, or some modern analogue thereof, which is lacking in the
modern concept of adaptation, or better, of the organism as a pure aggregate of
adaptive mechanisms. [23]
Let us look a bit more closely, then, at the relation
between modern biology and Aristotle’s concept of eidos.
Perceptions of form - the shape of an oak leaf, the
walk of a cat, the metamorphosis of a butterfly - the grasp of such
configurations and changes of configuration, are among the basic insights by
which the subject-matter of biology is singled out. A certain freedom of form within form, Buytendijk has shown, is the criterion by which we see a
shape as “alive.” [24] Biological
knowledge, the knowledge of men like Ray or Hooker, was a refinement of such
elementary perceptions, a refinement to the point of genius, but not different
in kind from its everyday counterpart. Modern biologists, however, at least the more theoretical, and more articulate, among them, sharply reject
such old-fashioned connoisseurship. Form, and the recognition of form, are not only not
(according to their own professions of faith) their central concern; they
exhibit a positive dread of form. In the
polemics that characterize contemporary taxonomy, for example, and in evolutionary
controvery also, the favorite epithet of the
combatants is “typology.” To call a man
a typologist is the worst insult you can bestow. [25] It is hard sometimes to
tell quite what is meant by the
23. Cf. T. Dobzhansky,
“On Some Fundamental Concepts of Darwinian Biology,” Evol.
Biol. 2 (1968), 1-33, where efforts are made, not wholly successfully, to
disentangle some of these concepts.
24. See my account in Approaches
to a Philosophical Biology (New York, 1969), Ch. 2, 74-75.
25. R. R. Sokal,
(‘Typology and Empiricism in Taxonomy,” J. Theoret.
Biol., 3
(1962), 230-67.
408
term; it is not necessarily Platonic realism,
perhaps something like Aristotelian realism. In any case, it’s deadly. Perhaps, indeed, it is most of all this eidophobia, if one may so christen it, that makes biologists shudder at the very name of
Aristotle. Yet the Aristotelian concept
of eidos could teach reflective biologists
much about the foundations of their discipline.
Eidos in
Aristotle is used differently in different contexts, but when used technically
it seems to represent a single concept, although it is already rendered in
Latin (as in modern European languages) by two separate terms: forma and
species. I have not found,
however, any indication that Aristotle took the term eidos
to be in any formal sense equivocal. Thus he includes genos,
for example, in the philosophical dictionary (Delta 28), but uses eidos in that discussion as if there were no
problem about its meaning. [26] Since
he deals so carefully with the several meanings of equivocal terms, I can only
conclude, therefore, that he thought of eidos
as one comprehensive concept, with different applications in respect to
different problems, and perhaps with two major applications which correspond,
for us, to “form” and “species.” Or, if
even this partial separation is incorrect, we may separate, for ourselves, the
two aspects of his one concept when we try to see what it can tell us in the
context of modern biological methods. [27]
First, then, form in contrast to matter. Eidos in
this context functions in a number of striking respects in the same way as the
concept of organization (or information) in modern biology.
a. For one thing, form and matter in Aristotle constitute a pair of concepts used relatively to one another and relatively to the problem at hand in a great variety of different contexts. The eidos of an entity or process is its organizing principle, the way it works to organize some substrate capable of such control. Though it is sometimes equiva-
26. For a detailed account of
Aristotle’s usage in his own biological writings the reader should consult
Professor David Balme’s definitive treatment, as well
as A. L. Peck’s notes in the Introduction to his edition of the Hist. Anim. D. M. Balme, “Telos and Eidos in Aristotle’s Biology,” Class. Quart.
12 (1962), 81-98; A. L. Peck, Introduction, in Aristotle, Hist. Anim., volume
I, (Cambridge, Mass., 1965) esp. notes 5-11. Cf. also D. M. Balme,
“Aristotle’s use of differentiae in zoology” in Aristote
etles Probièmes deMéthode(Louvain, 1960) 195-212.
27. The two aspects I am
separating are, admittedly, brought very close together by Aristotle himself,
not only in Post Anal. (94 a 20ff.), where genos is given a place corresponding to that
of “material cause” in the Physics, but also in Metaphysics 1024b
8, Z 1038 a 6, H 1045a 23 f. and 11058 a 23, where genos
is identified with hyle. I am grateful to Professor Balme for calling my attention to the latter passages, and
confess that I might not have made the distinction between the two pairs of
terms as flatly as I tried to do, had I read his papers (just referred to)
before writing this essay. No one
interested in Aristotle’s biology and its relation to his philosophy of science
can afford to neglect Professor Balme’s careful and
illuminating work.
409
lent to morphe
or shape, that is by no means always the case. Nor is form in nature a separate,
self-subsistent “absolute”; on the contrary, it must once more be emphatically affirmed, it exists in, and only in, that
which it informs. In the context of the
entity or process in question it exists as the organizing principle of
that process, just as its matter exists as the potentiality of such (or other)
organization. Thus in noses (one of
Aristotle’s favorite examples) snub is the form of the matter flesh and bone. In bone, however, boniness is the form of
earth and fire or whatever elements compose it. Biological systems lend themselves par
excellence to this dual - but not dualistic - analysis. It depends on the particular system one is
studying what will be form and what matter in a given case; but the two-level
analysis is always apposite. On the one
hand, this matter as the matter of this form is by no means to be ignored,
since natural form exists only as actualized in an appropriate matter. As the matter of this form, indeed, it can be
studied with profit for itself - as modern biology studies, in much greater
exactitude than Aristotle could dream of, the physico-chemical
substrate of living systems. But the
form too can be studied for its own sake, as it is by modern systems-theorists,
even though it exists only as enmattered and depends
for its existence and continuance on the laws governing the matter of which it
is the form. And again, be it noted, if Platonists and scholastics generalized the Aristotelian
concepts to form a cosmic hierarchy from the abstraction of prime matter to the
Divine Mind, this was not Aristotle’s primary intent. Eidos
and hyle were
for him a pair of analytical tools, to be applied in the study of nature relatively
to one another and relatively to the particular inquiry.
Despite the simplicity of his examples and the crudity
of his “chemistry,” Aristotle’s methodological thesis is an important one. Eidos in
the sense of organizing principle is indeed a definitive concept for biological
method. True, in view of the advance of
scientific knowledge since Aristotle’s time, its modern counterpart is couched
in very different terms. Thus, for
example, G. L. Stebbins in his Basis of
Progressive Evolution describes the principle characterizing living systems
as that of relational order. “In living
organisms,” he writes, “the ordered arrangement of the basic parts or units of
any compound structure is related to similar orders in other comparable
structures of the same rank in the hierarchy, permitting the structures to co-operate
in performing one or more specific functions.” [28]
This is a much more precise statement,
indeed, but it plays the same role relative to the chemistry and physics of
living things as does Aristotle’s concept of form in relation to matter. The colinearity of
the DNA chain is a relatively simple example of such order. The concept of information may also play a similar
part. In fact, it is even closer to
28. G. L. Stebbins,
Basis of Progressive Evolution (Chapel Hill, N.C., 1969), 5-6.
410
Aristotelian form. For information can be found in any sort of
system (and any system, in Aristotle’s view, can, and should, be studied in
form-matter terms), yet in living things the quantity of information is vastly
greater - and more interesting - than in non-living systems. [29] From this point of view,
indeed, Raven’s “Formalization of Finality” might better be called “The
Formalization of Form.” Just as, from
the Aristotelian scientist’s point of view, matter is the possibility of
taking on one form or another, so the elements of an information-bearing system
can assume any one of many equiprobable states, one
of which, by virtue of its very improbability and in proportion to that improbability,
becomes a bearer of information. In
short, the relation between entropy and negentropy in
biological processes expresses a quantitative equivalent of Aristotle’s
qualitative distinction between the material and formal aspects of a given
system or subsystem, of an organism, organ system, tissue, etc.
b. As either of the instances just cited indicates,
moreover, (that is, Stebbins on relational order or
Raven on the information-theoretical aspect of biology), the role in biology of
a concept of form, organization or information should demonstrate once for all
the irreducibility of biology to physics and chemistry (at least in their
classical, reduced, and one-level form). This was Aristotle’s thesis also, against
Democritus. Organized systems cannot be
understood in terms of their least parts alone, but only in terms of those
parts as organized in such systems. Organized systems are doubly determinate; they
exist on at least two levels at once. True,
the form-matter pair of concepts do not of themselves generate a stratified cosmos;
but they do show us how to resist reduction to one single cosmic
level, whether of Democritean atoms or of the
fundamental particles of modern physics. There may or may not be a cosmic hierarchy;
the fact remains that whenever we study living systems we are studying
particular, limited systems that are hierarchically organized, organized on at
least two levels. We are studying
systems composed of elements obeying their own laws, but constrained at the
same time by arrangements of those very elements which constitute, as such,
laws of a higher level. The
29. The locus classicus for the application of information theory in
science is Science and Information Theory, Leon Brillouin,
(New York, 1956). The application of
information theory to biology has been discussed in a number of places, notably
by Henry Quastler, see The Emergence of Biological Organization (New
Haven, 1964). The point that the
distinction between living and non-living systems with respect to information
is quantitative - though great enough to appear qualitative - I owe to Dr.
Thomas Ragland of the University of California, Davis, who has lectured on this
subject to my class in the philosophy of biology. Michael Polanyi, in “Life’s Irreducible
Structure” (in Knowing and Being [Chicago and London, 1969], 225-39),
argues, on the contrary, that the distinction between the two kinds of systems
is logical and qualitative; yet he admits, in terms of evolution, a continuous
transition from one to the other.
411
higher level - form, organizing principle, code, fixed action pattern
or what you will - exists only in its elements, and depends on them for
its continuance, yet the laws of the elements in themselves, corresponding to
Aristotelian hyle, permitting any
number of informing arrangements, do not as such account for the principle
which in this case happens to constrain them.
If, moreover, the question of teleological explanation
left us puzzled, here, it seems to me, the case for non-“mechanistic” explanation
becomes much clearer. The concept of eidos, like that of telos,
is indispensable to help locate a biological problem: it has heuristic value.
If used with good judgment it locates,
as telos does in limited areas, a real
phenomenon, a structure or process, in nature; it has descriptive value.
But much more clearly than telos, it also has explanatory power. To discover the working principle of an
organized system, as in the specification of the DNA code, or in the functional
explanation of the lateral line (apart from the question of its origin), is to explain
the system just as truly as one explains it by analyzing its physico-chemical parts. To learn how an organized system operates is
just as conducive to the understanding of it - the scientific understanding
of it - as is the analysis of the same system into its elementary components. Indeed, the teleonomic
study of biological systems is probably reducible, I would suggest, to the
diachronic rather than the synchronic study of their form. Teleonomy sits
uneasily on evolutionary theory, one would then suspect, because, since the
sequence of living systems that have inhabited this planet does not itself constitute
a living system, it has no eidos, and
therefore no telos, to which the study
of its necessary conditions could be referred.
c. Biological explanation, then, works in terms of
form or matter, systems-theoretic study of wholes or part-analysis
(ultimately physico-chemical) of their constituents,
with the two kinds of explanation complementing one another. That complementarity,
thirdly, however, is not symmetrical. Again,
there is a striking resemblance here to the Aristotelian form/matter pair. All natural things, organized parts of such
things and processes exhibited by them, are inherently informed matter and can
be studied on both levels; but form is prior. In non-Aristotelian language: although the
upper level of a doubly determinate system depends on the lower level, and the
laws of the lower level, for its existence, and is inseparable from it, it is
the upper level that makes the system the kind of system it is. We have to refer to the upper level, we have
seen, to generate a problem, to describe the system we are studying, and in
certain cases at least to explain the operation of the system as such. Thus in the code case or in physiological
explanation, the problem-location, the description and the explanation
all refer to form: information. In some
cases perhaps only the first and second obtain as explanatory principles. Research
412
on the lower level, physics in relation to molecular biology, or physiology
in relation to behavior, or chemistry in relation to metabolism, may indeed go
on indefinitely without explicit reference to the higher level, the structure
of an enzyme, the typical course of a nesting behavior, the normal growth
process of an embryo; but it will not be study of this system without
some implicit reference at least to the organizing principle concerned. The higher level, though dependent on the
lower, is both epistemologically and ontologically prior to it. For Aristotle, of course, it is also prior in
time: man begets man eternally. That is
what evolution has altered: for us potency is, in nature as a whole, prior to
actuality. But given the existence of an
organized being or process, form is then prior to matter, not only cognitively
but onto-logically as well. Prior
cognitively: to know the system is to identify, describe, and understand it in
terms of its operating principles, of the way it uniquely constrains its
components to make this system of this kind. Prior ontologically: since the principles
of “matter” on their own could logically, and in terms of the laws of
probability, take on any “form,” it is the existence of this form that
makes the system what it is.
Once more, of course, we are talking about relative
levels of a system or subsystem e.g., organic bases vs. their arrangement
in a code, or the reactions entered into by chemical trace elements vs. the
structure of the metabolic pathways in which they serve. Whatever system or subsystem we happen to be
attending to in a given inquiry, however, this relative priority of the higher
level obtains. One might call this
relation, as I have suggested elsewhere, a principle of ordinal complementarity. [30] Aristotle understood it
well.
d. Finally, there is a special area where the Aristotelian
concept of form has proved strikingly parallel to some aspects of modern
thought: that is, in his doctrine of soul, the form of organized bodies. We may leave the vexed question of active
reason aside and note briefly two theses in Aristotle’s “psychology” to which
modern reflection about biology seems to be slowly and painfully returning.
First, Aristotle’s concept of psyche as such is
functional. This is a concept of mind
suggested by thinkers as different as Putnam, Ryle,
and Polanyi. [31] Polanyi
puts this thesis in his essay, “Logic and Psychology,” in terms of his
distinction between focal and subsidiary awareness. We can formulate the distinction between mind
and body, he says,
as the disparity between the experience of a subject
observing an external object like a cat, and a neurophysiologist observing the
bodily mechanisms by
30. The Knower and the Known, 233.
31. Hilary Putnam, “The Mental
Life of Some Machines,” Intentionality, Minds and Perception (Detroit,
1967), 177-200; Gilbert Ryle, The
Concept of Mind (London, 1949); Michael Polanyi, op. cit.
413
which the subject sees the cat. The experience of the two is very different. The subject sees the cat, but does not see the
mechanism he uses in seeing the cat, while, on the
other hand, the neurophysiologist sees the mechanism used by the subject, but
does not share the subject’s sight of the cat... to see a cat differs sharply
from a knowledge of the mechanism of seeing a cat. They are a knowledge
of quite different things. The perception
of an external thing is a from-to knowledge. It is a subsidiary awareness of bodily
responses evoked by external stimuli, seen with a bearing on their meaning
situated at the focus of our attention. The neurophysiologist has no experience of
this integration, he has an at-knowledge of the body
with its bodily responses at the focus of his attention. These two experiences have a sharply different
content, which represents the viable core of the traditional mind-body dualism.
“Dualism” thus becomes merely an
instance of the change of subject matter due to shifting one’s attention from
the direction on which the subsidiaries bear and focusing instead on the
subsidiaries themselves. [32]
Thus, mind is not a separate something but is what Ryle
calls “minding.” It is the higher-level,
operating principle of a complex system:
Some principles, - for example, those of
physics - apply in a variety of circumstances. These circumstances are not determined by the
principles in question; they are its boundary conditions, and no principle can
determine its own boundary conditions. When
there is a principle controlling the boundary conditions of another principle,
the two operate jointly. In this
relation the first can be called the higher, the second the lower principle.
Mental principles and the
principles of physiology form a pair of jointly operating principles. The mind relies for its working on the
continued operation of physiological principles, but it controls the boundary
conditions left undetermined by physiology. [33]
This approach is generalizable, moreover, to
living things as such. In general the
“soul” of any living thing is its style of operating on and in its environment,
no more, but also no less.
Secondly, the “kinds” of “soul” distinguished by
Aristotle appear to correspond in general to the major divisions which, however
we see the problem of “higher” and “lower” among organisms,
do in fact seem to obtain. If we look,
independently of any special theory of the how of evolution, at its
general course, we find, I think, three and only three really “surprising”
“advances.” First, there is the origin
of life. Here we get what Aristotle
calls “nutritive soul.” Living things
grow and reproduce. These are the
minimal functions of all life. Secondly,
living things acquire the principle of sentience and self-locomotion. This is “sensitive soul.” We get organisms capable of behavior, centers
of irritability, appetite, and self-motion. And thirdly we have the origin of man, of
culture, of the human social world, of what Aristotle calls “passive reason.” Surely these steps,
32. M. Polanyi, “Logic and
Psychology,” Amer. Psychologist, 23, (1968), 39-40.
33. Ibid.
414
distinguished by Aristotle, are just those
that may well puzzle the evolutionary theorist. [34] These are very crude
distinctions if you like, but it may be worth noting that with painful
deviousness we are coming back to the simple divisions in the levels of
organization in the world around us which Aristotle had recognized long ago,
divisions which he made, as we are trying to do, not dualistically, like Plato,
but in terms of function, of the inherent organizing and operating principles
that mark off kinds of complex systems as unique.
So much for eidos
in contrast to hyle. What about eidos
in contrast to genos? It is here that the opposition to
Aristotle is centered. For if modern
biologists in fact use concepts like organization and information in ways that
resemble Aristotle’s use of “form” in the form-matter pair, they strongly
object to the Aristotelian species concept, even though in Aristotle this
appears to be, if not the very same concept, at least the same concept under
another aspect. I want to make two
points in this connection: first, to indicate how the use of the species
concept in modern biology does still resemble the Aristotelian, and secondly,
to explain, or at least to locate clearly, the modern resistance to Aristotelian
thinking on this score. Again, however,
let me reiterate briefly what I said at the outset about the different
cosmologies associated with the ancient and the modern view. Aristotelian species are certainly eternal,
modern species certainly are not. This
meta-scientific contrast should not be underrated. A modern biologist can no more be a complete
Aristotelian than he can be a complete Cartesian. Yet in the routine use of the species concept
there is nevertheless a residual, though not a merely vestigial, similarity,
and at the same time, in the epistemological foundation of that use, a very
deep-seated contrast.
First, the similarity. Eidos and
hyle form, we have seen, throughout the
range of Aristotelian sciences, an analytical pair to be used relatively to one
another and to the subject matter in question in a particular investigation. When it comes to the eidos/genos
contrast, however, eidos assumes a
different and less relational aspect. (This
holds, I think, even if we admit that genos
means hyle, as it sometimes does; see note
27.) Only individuals are real for
Aristotle - the modern biologist would agree - but they are individuals of such
and such a kind. The infima species, like any form, exists only
in, and as form of, the individuals who exemplify it. The species is the sum total of its specimens,
past, present, and future, and they are the individuals they are in virtue of
their membership in that species. But
there is nothing relative about this. Eidos interpreted as species takes on an
absolute character which, in the natural world at least, eludes eidos as paired with hyle.
This of course, in its explicit
enunciation at least, is just
34. Cf. for example, the
obscure but thought-provoking argument of David Hawkins in The Language of
Nature (Garden City, N.Y., 1967).
415
what modern taxonomists, whether evolutionists
or pheneticists, so stoutly object to. And yet practising
taxonomists of whatever school do in fact continue to
treat “species” as having a special role, a role in some way less conventional
and closer to the real ways of nature than the concepts designating “higher
categories.” True, as Simpson points
out, all categories are “objective” in that all taxa
are collections of real organisms. And
they are all “subjective” insofar as they are all concepts in the minds of
taxonomists. Nevertheless, he admits,
“species” is more clearly “non-arbitrary” than other categories. [35]
Admittedly, some biologists, from Darwin himself to
Ehrlich and Holm, have predicted that the species concept would wither away and
we should be left with a classless aggregate of biological particulars. [36] Yet biologists still
classify and argue about the foundations of such activities; and in the view of
most of them the species concept has been refined, indeed, even transformed out
of recognition, but not abolished. Perhaps
this is correct. Certainly, the
“biological species concept,” defined in terms of potentially interbreeding Mendelian populations, or the “multi-dimensional species
concept,” tailored for the inclusion of non-sexually reproducing as well as of Mendelian populations, looks at first sight very unlike the
traditional originally Aristotelian, concept. [37] I want to point out only
that it is not as wholly unlike as it is usually painted.
Aristotle is usually accused of tagging species by
means of one single character selected a priori and abstractly. [38] This is unfair. He is certainly no a priorist.
Again, modern science had to reject
him at its outset because he was not “a prioristic”
enough: he stayed too close to the concrete pronouncements of everyday experience, he was too good an empiricist. [39] And even though he writes
in the Topics of, and is perpetuated in the tradition as insisting on,
definition per genus et differentiam, he
himself suggests both in the Post. Anal. and in De Part. Anim. that the “substance” of a thing (ousia) or its nature cannot
be captured by specifying any one differentia alone. [40] Indeed, his opposition to
Platonic “division” is based at least in part on the insistence that we divide
up natural things as nature demands, not by one character and its contrary, but
by the cluster of characters which helps us to single out a natural kind within
a larger group. [41]
35. G. G. Simpson, op.
cit., 114.
36. Darwin, Origin of
Species, Ch. XV (“species are only well-marked varieties”); Paul R. Ehrlich
and Richard W. Holm, “Patterns & Populations,” Science, 137 (1962), 652-57.
37. See Ernst Mayr, Animal Species and Evolution (Cambridge,
Mass., 1969), 18-20.
38. See e.g., Simpson, op.
cit.
39. See Portrait of Aristotle, esp.
Ch. III, and Wieland, op. cit.
40. Post. Anal. II, 13, 96a33 if. and
Part.
Anim.
634b29ff.
41. Part. Anim., loc. cit.
416
In this piecemeal and empirical approach to
classification he is not so different from modern
taxonomists as it is now fashionable to consider him. And again, like modern biologists, he is
driven, despite his insistence that only individuals are real, to grant to the
species concept some kind of uniqueness, as the least and most “real” of universals.
In short, it is in eidos
as species that the relativity of form is somehow or other anchored in
reality.
Just how this anchoring comes about is hard to say. Just how is the relational concept which we
render “form” to be identified with the non-relational concept called “species”
in the inclusive but univocal concept eidos?
I can give no satisfactory answer,
but only suggest the location of an answer in the even more puzzling conception
of the [HHC: Greek not reoproduced], which I
shall discuss briefly in the concluding sections of this paper. Even more difficult would be the task of
specifying the lesson to be derived for modern biology from the
plurality-in-unity of Aristotelian eidos. I can only register tentatively the
suggestion that one might profitably reflect on the link, whatever it turns out
to be, between organization or information on the one
hand and species on the other.
Biologists study throughout the widely varying phenomena
of living nature the organization of systems or subsystems at any number of
levels. Living things, as
information-bearing systems, have arisen gradually from non-living systems much
poorer in information content, and, once evolved, they continued to vary
continuously, to throw up, in correlation with their changing environments,
myriad new patterns in every conceivable direction of novelty. At the same time, there are cuts in this
continuum, not only the infinite number which we might make anywhere, but a few
(in relation to the infinite possibilities) which present themselves as preeminently
“natural” or, in Simpson’s term, “non-arbitrary.” These we designate as cuts between “species”
that is, between carriers, for a time, of distinctive patterns of information. One can study the organization of any
organized system or subsystem, of chloroplasts, cell membranes, muscle cells,
populations of genes, populations of whole organisms, communities of
populations of many species, etc., etc., but there are also some points at
which the transfer of a stable pattern of organization (or information) from
one living individual to another stops - stops “really,” not because we decide
to stop analyzing just there, but because there is a gap, a real discontinuity.
To populations confined by these plain
discontinuities (plain at least in sexually reproducing organisms with a
relatively long generation span), [42] we
give the same
42. For the complexities,
e.g., of bacterial taxonomy, see Mortimer P. Starr and Helen Heise, “Discussion,” Systematic Biology, Nat. Acad. Sci. publication 1962 (1969), 92-99.
417
name that Aristotle gave them; eidos, species, the very name he gave to
organization, eidos, forma. But here we are not, as in multi-levelled analysis of forms and their matter, singling out
such patterns as we discover by applying “form” and “matter” as shifting and
relational tools for our own study of nature, tools that locate form-in-matter
here, there, and everywhere. We are
finding certain forms singled out for discontinuity within the continuity of
the phenomena, as it were, by nature itself. It may of course be objected, as Simpson
remarks about higher categories, that in a sense all forms discovered everywhere
are equally objective. Every cell is
really bounded by a real membrane: the cytologist studies in the parts of one
kind of organism the structures of cells as such. Geneticists study drosophila not because the
species of that genus are themselves of greater intrinsic interest than
elephants or antelopes, but because they are good experimental subjects and so
from them much can be learned about the organizing principles of all heredity. Yet there is something unique - even
uniquely obtrusive - about species. The
developmental biologist - as distinct from the old-fashioned zoologist or
botanist - studies organized processes that range much farther than any given
species, or even phylum or kingdom. Yet
even he has to select, and learn to know, some species in order to study
in it the universal life pattern that interests him. [43] Much as he would like to,
he cannot evade these fundamental gaps. In practice he is still an Aristotelian in
spite of himself.
Yet in their attitude to taxonomy, ancients and
moderns are very different. If forms are
really pinned down into discontinuous species in a fashion not so very unlike
that recognized by Aristotle, why should modern biologists so emphatically deny
that any shadow of Aristotelian thinking lingers in their own methods? Partly because they take a
crude and truncated “Aristotelianism” as identical
with the thought of Aristotle himself. But there is another and more deep-seated
reason, and that concerns, in Aristotle, the relation of knowledge, especially
the knowledge of species, to perception. Modern science, let us recall once more, began
by rejecting the Aristotelian approach to nature, in part at least because it
was too directly tied to everyday perception of natural entities and processes
and so prevented the flights of abstractive thought and creative imagination on
which, as we can now see, the development of science largely depends. [44] The ideal of “scientific
method” for many philosophers and
43. Professor Dennis Barrett
of the Davis zoology department, while denying that he is a “zoologist,” admits
sadly that he has to know “his” organism, the sea urchin, in order to study in
it the development of the fertilization membrane.
44. Such founders of modern
science as Harvey and Newton, indeed, thought they derived their great
discoveries very directly from experience; we, with three centuries of
hindsight, know they were more daringly imaginative than they believed.
418
scientists has become the correlation, not of perceptions, usually directed
as they are to complex, concrete individuals, but of sheer particulars, of
“hard data,” with abstract laws, whether universal or statistical: correlations
peculiarly susceptible, it seems, to quantitative manipulation and experimental
control. For Aristotle, on the contrary,
knowledge, however theoretical, is rooted in the full, concrete, perceptual
world; it analyzes that concrete world and gains new insight into it, but never
leaves it as ultimate, as well as initia1, dwelling place. Now such perceptual insight is indeed
essential to certain kinds of biological practice: from the macroscopic
recognition of specimens in the field to the recognition of structures in electronmicrographs. The late C. F. A. Pantin
called such biological connoisseurship “aesthetic recognition.” [45]
The
double meaning of “aesthetic”: informal or connoisseurlike
on the one hand, and having to do with “aesthesis,” perception, on the other,
should be kept in mind in considering what this means. Pantin recalls, for
example, seeing a worm in the field and saying, “Why, that’s a Rhynchodemus, but it’s not
bilineatus,
it’s an entirely new species.” This,
he points out, is not the yes-no procedure of the museum taxonomist, nor does
it resemble at first sight the generalizing procedures of the exact scientist. [46] It is, precisely as for
Aristotle, a case of seeing a this-here as a such-and-such - or in this case, not quite a such-and-such
but a somewhat-different. But
just such perceptual recognition of real kinds is what modern theorists profess
to abhor. They seek to produce
scientific knowledge in an abstracter and more completely specifiable way. Scientific knowledge has its pedigree, they claim,
by mathematical thinking out of bare particulars, rather like Love in Diotima’s story, who was begotten by Resource on Poverty.
This distrust of anything but bare particulars on the
one hand and high flights of theory on the other comes clearly into view in the
contemporary taxonomic controversy between the phenetic
and phylogenetic schools. [47] The pheneticists profess to take all and any particulars,
without prior weighting derived from taxonomic skill and experience, feed them
into computers (those praiseworthy inorganic animals) and come out with
classifications better (for what purpose?) than those derived from less
restricted starting points and less quantitative manipulation. If they sometimes admit sadly to producing by
this method something justifiably called “types,” they are at any rate, they
claim, “empirical typologists,” with no
initial predilection
45. C. F. A. Pantin, “The Recognition of Species,” Science Progress, 42 (1954), 587-98; cf. his posthumous
Tamer lectures, The Relations between the Sciences (Cambridge, 1965).
46. “The Recognition of
Species,” 587.
47. D. Hull, “Contemporary
Systematic Philosophies,” Annual Review of Ecology and Systematics,
1(1970), 19-54 and M. Starr and H. Heise,
op.
cit.
419
for one cluster of characters rather than
another. Phylogeneticists,
on the other hand, hasten to cover their undoubted, but theoretically suspect, taxonomic
insights, derived from the aesthetic recognitions of field experience, under
the convenient bushel of evolutionary descent. Darwinian-Mendelian
theory, in other words, serves them as an abstract and therefore scientifically
respectable cover for their delicate perceptual discriminations: for the
.heritage of Ray, Hooker, and even, on the side of biological practice as
against theory, of Darwin himself. Particulars
tied together by computer techniques, says the one side; particulars tied
together, says the other, by lines of descent inferred though necessarily
unobserved. Some writers, notably
Gilmour, try to go between the horns of the phenetic-phylogenetic
dilemma by espousing a pleasant pragmatism. [48] We
classify as we need to for our uses, says he; as the use shifts, so does the
classification. This easy way out,
however, while correct in a way, since there are of course many possible
classifications of anything for many possible uses, fails to still the
controversy. For it
neglects the fact that some classifications do seem to be, quite apart from our
wants and uses, less arbitrary than others. To give due weight to the role of aesthetic
recognition in taxonomy, I submit, and to acknowledge its rootedness
in the perception of real this-suches, would
permit taxonomists to make more sense than they have recently done of the real
nature of their calling.
It should be duly noted, in passing, that the
grounding of scientific knowledge, and especially of scientific discovery, in
perception (rather than in sensation or the bare observation of bare
particulars) is beginning at last to be acknowledged by philosophers of
science. In a general way, perception as
the paradigm of discovery was the Leitmotif of Hanson’s writing. [49] The “primacy of perception”
as our chief path of access to reality was the central theme of Merleau-Ponty’s work. [50] A similar theme dominates
Straus’s phenomenology. [51] And in Polanyi’s Personal
Knowledge, Tacit Dimension, and other essays, both earlier and more recent,
one has, as distinct from those more general intuitions, a carefully
articulated epistemology which explicitly makes of perception, understood in a
Gestalt-cum-transactional fashion (not unlike Aristotelian aesthesis), the
primordial and paradigm
48. J. S. L.
Gilmour, “Taxonomy,” Modern Botanical Thinking (Edinburgh, 1961), 27-45.
49. N. R. Hanson, Patterns
of Discovery (Cambridge, 1965). Cf.
also his posthumously published Perception and Discovery (San Francisco,
1969).
50. M. Merleau-Ponty, La Phénoménologie
de la Perception (Paris, 1945), trans. by Cohn Smith, The Phenomenology
of Perception (New York and London, 1962).
51. See E. W. Straus, The
Primary World of Senses, trans. by J. Needleman (New York, 1963) and Phenomenological
Psychology, trans. in part by Erhing Eng (New
York, 1966).
420
case of knowing, and explicitly makes the
achievement of perception the primordial and paradigm case of discovery. [52] These lessons are beginning
to have some impact on philosophers of science, especially on those who base
their philosophy largely on physics. But
biology, from which, through Aristotle’s biological practice, the
acknowledgement of the primacy of perception took its start, still (with a few
honorable exceptions like that of Pantin) stubbornly resists this fundamental insight.
I am not, of course, alleging that perception in its
newly-discovered role plays the same part as it did in Aristotelian
science. It was the basis, and
the home, of discovery and of knowledge; it is the primordial case of
discovery and of knowledge, and all discovery and all knowledge are structured
as it is. In Polanyi’s terms: in all knowledge, as in perception, we
rely on subsidiary clues within our bodies to attend focally to something in
the real world outside. However
“abstract” that something be, both the bodily base and the
from-to structure characteristic of sense perception persist. In the present context: there is no disgrace,
therefore, in acknowledging the perceptual skill of field naturalists and
taxonomists as part of science. It is
not a “primitive” survival, but a visible analogue of the achievement of
knowledge, the paradigm case of our way of gaining contact with reality.
Let me return now to the question raised earlier: how
does eidos as the correlate of genos escape the relativity of the eidos/hyle pair? What is unique about species that makes
it the paradigm case of natural form? Here we come to that most idiosyncratic of
Aristotelian terms: the [HHC:
Greek not reproduced], what it is for a such-and-such to be a
such-and-such. “Essence,” with its
age-old accretions of misleading connotations, is a poor translation of
Aristotle’s phrase; perhaps “being-what-it-is” is the best one can do. [53] When one speaks of
“form,” this is what one’s discourse is aiming at; the form of a given kind of
thing is just what it is for that thing to be the kind of thing it is.
According to the Topics, the “being-what-it-is”
of a kind of thing is what its definition designates. Indeed, a definition is there defined as “a
phrase indicating the being-what-it-is.” To some interpreters, therefore, [HHC: Greek not reproduced] appears
to be primarily a logical term. Aristotelian
science starts from first principles, including real definitions. These specify, among the properties of a
thing, certain characters which are “essential” to it, and that means
characters which
52. M. Polanyi, op. cit., also
The Tacit Dimension (Garden City, N.Y, 1966). Cf. William T. Scott, “Tacit Knowing and The Concept of Mind,” Phil. Quart. 21(1971), 22-35.
53. Cf. “What-is-being,” the
rendering of Joseph Owens in his Doctrine of Being in the Aristotelian
Metaphysics (Toronto,
1957).
421
can be deduced from the initial predicating
statement. Definitions, in other words,
are premises of scientific demonstrations, and the [HHC: Greek not reproduced] is of interest as the
reservoir, so to speak, from which the predicate of such a premise can be
drawn. [54] Such
a rendering seems to bring the Aristotelian approach close, in form at least,
to the so-called “hypothetico-deductive method.” It must of course be noted, however, that
Aristotelian demonstration is anchored, through nous,
in the direct, “intuitive” knowledge of first principles. It is not, like dialectical syllogism, merely
hypothetical. Yet there is a parallel. For in both cases it is the deduction of some
properties from others that is chiefly of interest, and the [HHC: Greek not reproduced] is
thought of in this context as ancillary to this primarily logical game. So far as the importance of deductive method
goes, Aristotle himself, at least in his logical writing, certainly reinforces
this impression.
Yet if one searches the corpus for scientific
demonstration, one finds relatively little of it. Most of the arguments of most of the treatises
do not look like assertions of defining phrases followed by deductions from
these. Most of them appear to be not
strictly demonstrative, but inductive, dialectical, or aporetic.
They move from common experience or
common opinions, weighing the views of others, analyzing difficulties, in the
hope, it seems, of arriving at (not starting from) an insight into some
specific nature. This searching nature
of much of Aristotle’s writing leads W. Wieland to a
different interpretation. For him the [HHC: Greek not reproduced] is
not so much a guide to definition, and therefore to demonstration, as it is a
heuristic tool, a topos or path along
which the thinker may seek insight into some special problem. [55]
For form and matter this heuristic or methodological
interpretation is indeed fruitful, as I have emphasized. Yet via form as species we have seen
that there is also a resting place for form-matter analysis, a place at which
form becomes uniquely non-relational. And
it is here that form exhibits its ontological foundation in “the
being-what-it-is” of each kind of thing, the very foundation which, according
to
54. The “logical” is one of
the aspects of the [HHC: Greek
not reproduced] distinguished by C. Arpe in
his dissertation, Das [HHC: Greek not reproduced] Aristoteles (Hamburg, 1937). Cf. E. Tugendhat, TA
KATA TINΣ (Freiburg/M’ünchen, 1958), 18, n. 18: Erst [HHC:
German not reproduced]. But cf.
also Wieland, op. cit., 174; the “logical”
here is perhaps closer to what I am calling the “methodological”
interpretation. It is closer to
heuristics - the search for principles - than to demonstration from them.
The deductive aspect is stressed by
Prof. Moravcsik in his reading of [HHC: Greek not reproduced] (oral
communication).
55. Wieland,
op. cit., pp. 174-75. Wieland emphasizes the
methodological function of the [HHC:
Greek not reproduced] (which he identifies, by implication, with Arpe’s “logical” function) to the exclusion of its other
aspects, esp. what Arpe calls the “physical” or
“teleological” and the “ontological.”
422
Aristotle, his predecessors lacked, the ignorance of which prevented them
from discovering the right method for the investigation of nature. Neither the logical nor the methodological
approach to Aristotelian science makes sense without this frankly ontological
foundation. The [HHC: Greek not reproduced] is expressly what definition
is about, both its target and its presupposition. Indeed, without the [HHC: Greek not reproduced] as the referent of
definition, the real being-what-it-is of this kind of thing which the defining
phrase designates, the demonstrations that follow on definition would be simply
“hypothetico-deductive” in the sense of positivism or
phenomenalism. They would not be rooted, as Aristotelian
science was certainly meant to be, in the natures of the things themselves, and
in our understanding of these natures. Without
the [HHC: Greek not reproduced]
as endpoint and foundation of inquiry, moreover, the inquirer would be
confined to an endless and directionless groping; but that is not the case. On the contrary, the real being-what-it-is of
the kind of entity under investigation is constantly guiding his search, and
directs it to its successful issue. Despite the apparent formal correctness of the
logical interpretation, therefore, and despite the importance of the
methodological aspect, the traditional ontological interpretation of the [HHC: Greek not reproduced] is
still fundamentally, sound. [56]
What does it teach us? We would not link the being-what-it-is of
things, as Aristotle did, to eternal kinds, nor would we restrict these “kinds”
to kinds of substance. Everything
becomes, including species; and what becomes may
as well be events or processes as more literally “things.” But despite these deep differences, there are,
I believe, two important lessons to be learned from the Aristotelian concept of
being-what-it-is as the designatum of definition and
the target of inquiry. Aristotle
understood, as most modern philosophers of science until recently have not,
that the investigation of nature arises out of puzzlement about some particular
problem in some limited area: nobody investigates, or can investigate,
everything at once. And in such an
investigation, further, it is the real nature of the real entity or process
that the investigator seeks, and sometimes finds. Science is pluralistic and realistic,
not uniform and phenomenalist, as modern
orthodoxy has supposed.
If we put these brief remarks together with our earlier reflections about form and matter, we find, in conclusion, three important methodological lessons to be derived from the study of Aristotle. Through the concept of form as an analytical tool, correlative with matter, Aristotle can remind us of the many-levelled structure both of inquiries into complex systems and of the systems themselves, and thus of the inadequacy of a one-levelled atomism for the understand-
56. See Arpe, op.
cit.. For a
clear summary of the traditional view, see Bernard J. Lonergan,
S. J., Verbum - Word and Idea in Aquinas (Notre
Dame, 1967), 16-25.
423
ing of such systems.
In conjunction with the grounding of
form in the [HHC: Greek not
reproduced] of each kind of thing, further, he can remind us of the
falsity of two other modern misconceptions: the unity of science concept on the
one hand, the claim that the subject-matter and method of science are
everywhere the same, and, on the other, the insistence that science must
renounce any claim to seeking contact with reality: that theories float, as
pure constructs, on the surface of the phenomena, with no mooring in the real
nature of the real events or things.
The first of these reminders is plainly related to the
concept of organization or information and hence (as I have already argued) to
the subject-matter of biology, and to the question of its reducibility or
irreducibility to chemistry and physics. The second reminder, of the plurality of
science, a reminder of the good Kantian principle [57]
that we can have no systematic knowledge of the whole of nature, should help
also to liberate biology, or thinking about biology, from the overabstract and reductive demands imposed by taking one
science, classical physics, as the ideal of all. And lastly, the acknowledgement of scientific
realism should release the biologist to admit the insights into the concrete
manifold of his subject-matter, from which his work originates and in which,
however abstract and sophisticated it may become, it still is anchored. Nor, finally, as I emphasized at the outset,
is this a plea for a return to Aristotelianism. It is a plea for us to listen, despite our
fundamental differences of metaphysic and of method, to some of the tenets that
Aristotle, as a biologist-philosopher, advocated long ago, and to try to
interpret them in ways that could be useful to us as we attempt to articulate
and revise our conception of what the investigation and the knowledge of living
nature are.
University
of California, Davis.
57. In a discussion of a
similar argument, Professor Günther Patzig has pointed out to me that the principle of the
plurality of science is non-, even anti-Kantian, if by it we mean to espouse a
plurality of scientific methods. For
Kant the method of science was indeed one. What is Kantian, however, is the denial
that we can have one unified, finished system of knowledge for the whole of
nature. If we could have such a system,
we could not have diversified sciences with diversified methods. If we cannot have such a system, on the other
hand, then a plurality of fields, and of methods, is at least logically
possible, and on Kantian grounds.
424