Embodied Animal Mind and Hand-Signing Chimpanzees

Chimpanzee language studies have generated much heated controversy, as Roger Fouts can attest from firsthand experience. Perhaps this is because language is usually considered to be what truly distinguishes humans from apes. If chimps can indeed be taught the rudiments of language, then the difference between them and us is not as great as we might have thought. It is a matter of degree rather than kind, a continuity, and our species is not so special after all. The advantage of this continuity thesis, as Fouts has emphasized, is that it conforms to the general tenets of evolutionary theory, and fits well with the evidence from paleontology and genetics that suggests that apes and humans are close cousins. It also has profound implications for the way we treat our primate relatives.

Opposed to continuity theories are those who posit a discontinuity between humans and apes, perhaps due to a “language instinct” (e.g., Pinker) or a specialized cognitive module. The advantage of this view is that it accords with prima facie observations that we humans are unique in our cognitive abilities, our complex cultures, our desire for meaning, our fondness for stories and rituals, and our tendency to ponder our ultimate fate. The problem with the discontinuity view is that it lacks an evolutionary explanation of how a new instinct or module arises, or exactly what these might be in terms of human biology. Perhaps more importantly, and as Fouts has pointed out, it tends to support the view that humans are special, and consequently reinforces, particularly in Western cultures, our domination over other species.

Parallel to the continuity-discontinuity debate is a dispute over how to interpret complex animal behavior. There are those who insist on being hard-nosed and, in the name of being scientific, avoid all mentalistic terms. But many people in both the sciences and humanities find such paradigms too restrictive to describe and understand complex animal behavior. They contend that since there is an evolutionary continuity between apes and humans, apes must be cognitive creatures in much the same way that humans are. Thus we can use terms from human folk psychology when talking about other animals. For some, this includes talking about animal consciousness. Fouts, I believe, is on this side of this debate.

Unfortunately, mentalistic and folk psychology views have their own problems. One is that they usually rely on a Cartesian and Lockean view of mind, something Fouts wisely wants to avoid. Mind is something non-physical “inside” the animal that forms representations of the outside world. Fouts contrasts a Cartesian view with Darwinian continuity; but affirming evolutionary continuity does not necessarily dispel Descartes’ delusion, which is mind-body dualism and a representational psychology. Applying a mentalistic folk psychology to animals risks foisting a quasi-Cartesian mind onto our animal relatives.

The second widely acknowledged problem with a mentalistic view of animals is anthropomorphism. This is where the debate can become particularly acrimonious. Is anthropomorphism scientifically legitimate? Can it be avoided? Is there good and bad anthropomorphism? Primatologist Sue Savage-Rumbaugh (1999) quite reasonably believes that we need to be anthropomorphic in order to find out whether apes can develop primitive language skills (168).¹ They will learn linguistic communication only if we believe they can. Imagine a human child growing up amongst adults who treated all of her linguistic behavior with skepticism. Anthropomorphism is also important for practical ethics: the more we see apes as being like us, the more likely we will be to support efforts to improve their conditions in captivity and protect them from extinction in the wild. This is the important practical thrust of Fouts’s work.

Fouts is right to be in the Darwinian continuity camp. I think it likely that researchers will eventually conclude that there is no special language instinct or even a distinctive cognitive module that separates human cognition from ape cognition. Still, the differences are so vast, at least on the surface, that they call for an explanation. This is largely lacking in continuity theories. With Fouts and others, I also believe that we need to understand animal consciousness...