A Deep Thinking

After Chris of Mixing
Memory and Deric
Bownds of Deric Bownds' Mindblog had already drawn attention to the prefinal
version of this article, “Darwin’s
mistake: Explaining the discontinuity between human and nonhuman minds” by
Derek
Penn, Keith
Holyoak and Daniel
Povinelli has now finally been published in the current issue of the Behavioral
and Brain Sciences.

Penn, who’s affiliated with the Cognitive
Evolution Group at the University of Louisiana, and the University of
California, Los Angeles, Holyoak, Professor of Psychology at the University of
California, and Povinelli, Professor of Biology at the University of Louisiana,
and also a member of the Cognitive Evolution Group, argue that

“Over the last quarter century, the dominant tendency in comparative
cognitive psychology has been to emphasize the similarities between human and
nonhuman minds and to downplay the differences as “one of degree and not of
kind” (Darwin 1871). In the present target article, we argue that Darwin was
mistaken: the profound biological continuity between human and nonhuman animals
masks an equally profound discontinuity between human and nonhuman minds. To
wit, there is a significant discontinuity in the degree to which human and
nonhuman animals are able to approximate the higher-order, systematic,
relational capabilities of a physical symbol system (PSS) (Newell 1980). We show
that this symbolic-relational discontinuity pervades nearly every domain of
cognition and runs much deeper than even the spectacular scaffolding provided by
language or culture alone can explain. We propose a representational-level
specification as to where human and nonhuman animals’ abilities to approximate a
PSS are similar and where they differ. We conclude by suggesting that recent
symbolic-connectionist models of cognition shed new light on the mechanisms that
underlie the gap between human and nonhuman minds.”

As was to expected the article sparked quite a lot of heated responses in the
comment section both for it’s title and for its discontinuist view of human
cognitive which emphasizes the large gulf that lies between human and nonhuman
cognition. Those who are afraid that again a creationist/ID paper has made it
into a respectable science journal, can calm down. In their first footnote Penn
et al. make clear that:

"All similarities and differences in biology are ultimately a matter
of degree. Any apparent discontinuities between living species belie the
underlying continuity of the evolutionary process and largely result from the
fact that many, and often all, of the intermediate steps are no longer extant.
In the present article, our claim that there is a “discontinuity” between human
and nonhuman cognition is based on our claim that there is a significant gap
between the functional capabilities of the human mind and those of all other
extant species on the planet. Our point, to cut to the chase, is that the
functional discontinuity between human and nonhuman minds is at least as great
as the much more widely acknowledged discontinuity between human and nonhuman
forms of communication. But we do not doubt that both evolved through standard
evolutionary mechanisms. (Penn et al. 2008: 129)

Interestingly, when you google “Darwin’s
mistake” your fist hit is an amazon link for a book called “Darwin's
Mistake: Antediluvian
Discoveries Prove Dinosaurs and Humans Co-Existed” to which I won’t link because
I don’t want to raise the page rank of such junk. The second link is a funny
little poem called "Darwin's mistake",
which goes like this:

I must say this poem is actually pretty funny (given that it's not meant as
anti-evolutionary propaganda), although, as primatologists and the Machiavellian
intelligence hypothesis tell us, non-human primates
surely
aren’t saints either.

But Penn et al. make their scientific standpoint absolutely clear with the
title of their response, which is called:

“Darwin’s triumph: Explaining the uniqueness of the human mind
without a deus ex machina”

I am particularly excited by the comment of Graeme Halford,
professor emeritus at the University of Queensland, Australia, and his
colleagues, who write that they

This of course reminds me of Karl Bühler’s (1934) coordinate system of
subjective orientation which I
tried to use as a starting point for
a cognitive theory which sees mental representations as intersubjectively
overlapping and thus shared systemic spaces in
the form of a cognitive coordinate system/frame of reference into which and in
which conceptual representations are imported, integrated, unified, and
blended. In the future, I will have another look at both Penn et al.’s and
Graeme Halford’s claims.

Another ‘interesting’ comment is that of R. Allen Gardner, a
Professor of Cognitive and Brain Sciences at the University of Nevada, Reno.
Here’s the abstract:

“Sound comparative psychology and modern evolutionary and
developmental biology emphasize powerful effects of developmental conditions on
the expression of genetic endowment. Both demand that evolutionary theorists
recognize these effects. Sound comparative psychology also demands
experimental procedures that prevent experimenters from shaping the responses of
human and nonhuman beings to conform to theoretical expectations.” (Gardner
2008: 135).

What now, you may ask, is ‘interesting’ about this article?. Well let’s take
a look at what agrdner had to say about another important Paper on the
difference between human and nonhuman cognition, namely Tomasello et al.’s
(2005): Understanding
and Sharing Intentions: The Origins of Cultural Cognition:

“Sound comparative psychology and modern evolutionary and
developmental biology (often called evo-devo) emphasize powerful effects of
developmental conditions on the expression of genetic endowment. Both demand
that evolutionary theorists recognize these effects. Instead, Tomasello et
al. compares studies of normal human children with studies of chimpanzees reared
and maintained in cognitively deprived conditions, while ignoring studies of
chimpanzees in cognitively appropriate environments.” (Gardner 2005:
699)

To me this sounds a bit like flogging a dead horse, but what do I know. (not
much about evo-devo, that’s for sure)

At least both feature this nice photo of the test apparatus for chimpanzee
Basso, who first was believed to be able to count but, as was found out in 1917,
instead was only reacting to the unconscious cues of the experimenter:

UPDATE:

Chris of
Mixing Memory, John
Wilkins of Evolving Thoughts and George
Junior have already posted about the article, I hope there are more to
come!

References:

Bühler, Karl (1934) Sprachtheorie. Die Darstellungsfunktion der
Sprache. Jena: Gustav Fischer.

Gardner, R. Allen (2005): Animal cognition meets evo-devo. In:
Behavioral and Brain Sciences 28:5. 699-700.

Gardner, R. Allen (2008): Comparative intelligence and intelligent
comparisons. In: Behavioral and Brain Sciences (31:2):
135-136.

Halford, Graeme S..Steven Phillips, and William H Wilson (2008):
The missing link: Dynamic, modifiable representations in working memory.
In: In: Behavioral and Brain Sciences (31:2) : 137-138.

Penn, Derek C, Keith J. Holyoak. and Daniel J. Povinelli (2008): Darwin's
mistake: Explaining the discontinuity between human and nonhuman minds. In:
Behavioral and Brain Sciences (31:2): 109-130.

Tomasello, Michael Malinda Carpenter, Josep Call, Tanya Behne, and Henrike
Moll (2005a): Understanding and Sharing Intentions: The Origins of Cultural
Cognition. In: Behavioral and Brain Sciences 28:5, 675–691