Eccles-iastical Dualism:
Review of Evolution of the Brain: Creation of the Self by John Eccles
Selmer Bringsjord and Joseph A. Daraio
Dept. of Philosophy, Psychology & Cognitive Science
Rensselaer Polytechnic Institute
Troy, NY 12180
USA
selmer@rpi.edu
daraij@rpi.edu
Copyright (c) Selmer Bringsjord and Joseph A. Daraio 1999
PSYCHE, 5(10), May, 1999
Previously Held: http://psyche.cs.monash.edu.au/v5/psyche-5-10-bringsjord.html
KEYWORDS: theory of evolution, mind, neuroscience.
REVIEW OF: John Eccles (1991). Evolution of the Brain: Creation of the Self.
Routledge, pp.282+xv, ISBN: 0-415-03224-5. Price: US$24.99 pbk.
1. Eccles is no Darwinian
Darwin might never have written Origin of Species (Darwin,
1859) had it not been for the arrival of a paper that shook him to the
core - a paper from Alfred Russel Wallace, wherein was set out, in
essentials, the very theory of evolution which Darwin had already
devised, but had not taken the time to refine and publish. In a flash,
Darwin took pen in hand, and hammered out the immortal book that would
supersede Wallace's work. All of this, of course, is but a tiny
chapter in the history of science - with which many readers are
doubtless familiar. Why mention it here? Well, Eccles calls himself
a Darwinian, but actually he's a Wallacean - and there's a
difference, a big difference between the two views. As Eccles explains, "Wallace felt that human intelligence could only be explained by the direct intervention of Cosmic intelligence" (Eccles, 1989, p. 235). This was a notion Darwin couldn't stomach. Wallace outraged Darwin by publishing a paper on primitive people (with whom he lived most of his life) in which he declared:
Natural Selection could only have endowed the savage with a brain a little superior to that of an ape, whereas he actually possesses one but a little inferior to that of the average members of our learned societies (Eccles, 1989, p. 235).
The notion that the powers possessed by homo sapiens sapiens (HSS) were created not by mindless processes, but by the Almighty, is one Eccles is quite at home with. Indeed, this book, despite it's empirical-sounding title, is in many ways a prolegomenon to Christian eschatology.
2. Eccles' Non-Darwinian Story
That this is so is not always clear; you have to read Eccles' entire
story, and you have to read it carefully. A casual reading may leave
readers with the impression that Eccles is a Darwinian; a careful
reading discloses the affinity to Wallace. We don't have the space here
to retell the story even synoptically, but we can convey its gist.
Eccles' starts spinning his narrative in the preface, where he informs
us that he has "been able to unfold the fascinating story of hominid
evolution of the human brain" (Eccles, 1989, xi). But we soon see that
there are two separate stories. The first spans the evolution of the
mammalian brain from the primates to the emergence of homo sapiens (HS).
The second story starts after the first ends, that is, after the brain
of HS had arrived; it's the story of how we became - to use Eccles'
phrase - human persons: incorporeal creatures able to control, and
have experience through, human bodies.
The first story is in many ways told from the point of view of a
detective recounting a solved case. Understanding the brain is made
possible by inference from clues - such as changes in posture and
locomotion. For example, Eccles infers from the famous footprints found
at the Laetoli beds in Northern Tanzania that Australopithecus (A) was
erect and bipedal. He also goes on to speak of human-like relationships
among A; this Eccles infers from hand-holding, which is in turn inferred
from the fact that the footprints in question are side-by-side. That
some of the footprints are superimposed one upon another implies, by
Eccles' lights, that A was capable of both a fairly high level of
concentration and fine motor control. Eccles makes similar types of
inferences from such evidence throughout the book.
Eccles' evolutionary story includes his discussion of the development of
fine motor control from early primates to HS in connection with
expansion of motor cortical representation for the thumb and fingers.
He tells us that it wasn't until these features of the brain evolved
that tool-making could occur. The idea is that the raw physical ability
was present, but there was inadequate brain power.
This raises the obvious question: Why did these features of the brain
evolve? In seeking an answer to this question one grasps the gist of
Eccles' narrative, and one begins to see that Eccles and Darwin are
worlds apart.
Eccles' answer to the question is that periods of stasis are punctuated
by periods of rapid evolutionary change (speciation events), but with
saltations and the creation of "hopeful monsters." He cites Eldredge
and Gould's (1972) theory of punctuated equilibria for support of his
saltatory view of evolution.<1>
The interesting thing about Eccles' view is that these changes have no
selective value, at least initially. It is only later that they may have
such an advantage. This phenomenon Eccles calls anticipatory evolution,
which is similar to what Gould and Vrba (1982) call exaptations. The
basic idea is that features that may presently have a function that
conveys a selective advantage for an organism may have arisen without a
selective value or may have had a previously different function then it
currently has. (See Gould and Vrba, 1982, for examples.) In a sense, the
new function arises by serendipity, but Eccles seems to hold that there
is indeed a reason for these changes, at least when it comes to the
brain. So first we have bodies able to walk erect in bipedal fashion,
and then comes the neural machinery able to control such bodies. And
first we have a hand physically able to build tools, and then comes the
neural machinery enabling the use of such a hand. And first we have
mechanisms allowing for the production of an array of sounds, and then
comes the neural stuff that can put these mechanisms to work in
communicating. In all these cases, the prior mechanism comes in order
to get ready for the subsequent neurological advance. The ultimate
trick of this type is the core of Eccles' second story: the advent of
dualist interactionism: the arrival of certain neural machinery in
primates makes it possible, many years later, for persons, existing in
the non-physical world of the mental, to interact with and control
bodies. Such an exotic and teleological scheme certainly isn't
Darwin's. It is Wallace's (Clements, 1983). As Eccles proudly confesses:
I believe that biological evolution is not simply chance and
necessity. That could never have produced us with our values. I can
sense with [Sherrington] that evolution may be the instrument of a
Purpose, lifting it beyond chance and necessity at least in the
transcendence that brought forth human creatures gifted with
self-consciousness (Eccles, 1989, p. 116).
3. Dualist Interactionism
What is dualist interactionism (DI)? In broad strokes, it's really no
mystery (in fine strokes, of course, it's nothing but mystery!): there
are minds, incorporeal entities, and they interact somehow with physical
brains. Nowhere does Eccles specify the interaction in question; and he
gladly admits that such specification is currently beyond
reach. However, he's well aware of the standard objection:
The materialist critics argue that insuperable difficulties are
encountered by the hypothesis that immaterial mental events such as
thinking can act in any way on material structures such a neurons
of the cerebral cortex... Such a presumed action is alleged to be
incompatible with the conservation laws of physics, in particular
of the first law of thermodynamics (Eccles, 1989, p. 187).
How does Eccles address this problem? By turning to quantum physics,
specifically to the work of Margenau (1984):
Following Margenau, the hypothesis is that mind-brain
interaction
is analogous to a probability field of quantum mechanics, which has
neither mass nor energy yet can cause effective action at
microsites. More specifically it is proposed that the mental
concentration involved in intentions or planned thinking can cause
neural events by a process analogous to the probability fields of
quantum mechanics (Eccles, 1989, p. 189).
Such a scheme isn't likely to make any philosophical headway, for the
simple reason that that to which Eccles appeals here (as physicists and
philosophers of science can confirm) is as controversial as
interactionism itself.
4. Arguments for Dualist Interactionism?
Eccles' book is shockingly short on argumentation; we imagine that
Eccles himself would confess that argumentation (at least of the
rigorous variety) isn't intended to be the book's strong suit. However,
a charitable reading (an extremely charitable reading) yields three
arguments that can be reconstructed from the text. They are:
A1 "The Brain Replacement Argument." The basic idea here is
that most of
your body is inessential. That is, we can cut off your foot, and
replace it with a prosthesis, or even just leave you without it (if
we take care of the bleeding). We can do this for your nose, your
eyeballs, your hair... in fact, we can clearly do it for everything
beneath your chin. And we don't even need to stop when we reach
your brain. As Eccles points out (Eccles, 1989, p. 219), removal of
the cerebellum gravely incapacitates movement, but the person is not
otherwise affected. So we can keep going at least until we get to
parts of your neo-cortex. Once at this point, we note that the
physical stuff in question can be replaced with other physical stuff
as long as the new stuff operates similarly - so how can a mind, a
person, as a genuine thing that persists through time (an ens per
se, to use the Latin), be a particular physical thing (an ens
successivum)?
A2 "The Argument from the Failure of Evolution to Explain X." The argument
here flows from a disjunction to the effect that every X is either
explained in natural terms by evolution, or in terms that invoke a
realm beyond the physical. Eccles intends that X be instantiated to
phenomenal consciousness (P-consciousness to use Block's term;
Block, 1995); and he maintains that such consciousness cannot be
explained in exclusively natural terms. If we have P-consciousness
(as it certainly seems we do), and evolution can't explain it, then
we seem to be sliding toward Wallace rather than Darwin: we seem to
be sliding toward an explanation that goes beyond nature toward
theism.
A3 "The `Looking-Down' Argument." Eccles says that he likes to imagine
himself floating above Earth, looking down on the drama of evolution
as it unfolds. The idea is supposed to be that when one engages in
this gedanken experiment, and imagines evolution sped up, it seems
implausible that this remarkable ascension from microbes to HSS
could have happened as a sort of cosmic fluke. For Eccles, this
"looking-down" perspective forces a Dramatist (with a capital, bold
`D') into the picture.
Are these arguments any good? A1, or at least sophisticated versions
thereof, is an argument that one of us (Bringsjord) has written a bit
about elsewhere (cf. Bringsjord, 1992, and Bringsjord and Patterson,
1995); the same goes for A2 (Bringsjord and Noel, forthcoming).
(Perhaps the most interesting instantiation of A2 [where X is set to
`cognitive faculties that search for and find true or at least
verisimilitudinous propositions'] is given by Alvin Plantinga, 1993.)
In general, Bringsjord finds both A1 and A2 quite promising (not only
because he finds Plantinga's argument formidable, but also because he
finds related arguments given by Roderick Chisholm (1978) to be
powerful). Daraio finds A1 and A2 weak, because he is inclined to
believe that there are naturalistic, evolutionary explanations for
personhood and consciousness, though he certainly concedes that no such
explanations are in hand.
A3 would seem to be a variation on the Argument from Design. For
example, presumably the most startling scene when one "looks down" is
that at turn after turn in the story of evolution, a fertile route
rather than a barren one is taken because of the particular value of
some tiny variable. As such, A3 probably stands or falls with the
modernized Argument from Design articulated by Leslie (1989).
But for Eccles (at least on a generous reading), A3 is more than a
thought-experimental version of the Argument from Design: standing
alone, the argument in declarative form is indeed supposed to deliver
the conclusion that evolution is God's grand design; but - and here is
the more interesting strand - the mere fact that we can articulate the
argument is supposed to be proof that lying beyond the physical world is
the world of mind. The notion behind this argument is that in order to
articulate A3 one has to use what Eccles calls "creative imagination;"
one has to "look down." Einstein, as much as anyone, employed this type
of thinking; as is well-known, he sought to "become," for example,
objects travelling at great speed (Einstein, 1952). Eccles holds that the
sort of cognition involved here is beyond the physical realm: it's an
activity of pure mind, not an activity to be identified with any brain
process. Since (as is the norm in this volume) no argument is given for
this view, readers are left to ponder whether there is anything to
recommend it.
And that's pretty much the upshot overall: an interesting book, yes, but
one that leaves the reader with a choice: since there are no arguments
to speak of, do I bother to consider whether the views advocated herein
can be established, or at least defended? Or do I place it in some
recess never to be retrieved, a tired, pontifical recasting of
Descartes' spooky theory of mind?
Notes
<1> By the way, this
seems to us to be a misunderstanding of Eldredge and
Gould's theory. Change may be relatively rapid in their scheme, but
they don't postulate that it's discontinuous.
References
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consciousness? In G. Mulhauser (Ed.), Evolving consciousness, New
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