Zombies

We’re all familiar with the kinds of zombies featured on AMC’s show “The Walking Dead”. Philosophers talk a lot about zombies, but not the kind that come after us to eat our brains. Philosophical zombies are hypothetical creatures that are indistinguishable from human beings (behaviorally and physically), but that have no inner thoughts, sense of awareness, or mental life whatsoever. Philosophical zombies talk like us, walk like us, and are even as intelligent as us. They also have brains and bodies just like ours. The only difference is that they lack a mind—there is nothing it is like to be a zombie. One of the big areas of dispute amongst philosophers of mind is whether or not such beings are conceivable.

Zombies were (re)introduced into the philosophical debate by the philosopher David Chalmers in his 1996 book “The Conscious Mind”. In his book, Chalmers argues that zombies are conceivable beings, and that our ability to conceive of zombies entails that that they are logically possible beings (i.e. their possibility involves no contradictions, unlike e.g. a married bachelor). Chalmers then argues that the possibility of zombies entails that physicalism—the view which states that everything in the world is physical in nature—is false, and that we should be dualists (i.e. there exists physical stuff + mind stuff). If there could be a physical duplicate of a conscious being without consciousness, then consciousness would be a kind of property that is not physical in nature. The conscious mind would then be something over and above the brain. Additionally, we would need some explanation for why we have consciousness in the first place. What’s the point of having consciousness if there could be creatures like us without it?

The major assumption running through the zombie argument is that consciousness is irrelevant to the guidance and execution of complex behaviors. One may interpret this to mean that mental states (e.g. beliefs, desires, feelings) do not serve a function and are thus epiphenomena. That is to say, our conscious mental states are just like the humming sound of a computer. They do not serve a purpose and do not add anything to the functioning of the systems. They are instead, mere byproducts.

One may very well want to challenge this assumption. Consciousness probably does have a function (Seth 2009). It seems to be a trait that would have been advantageous for our evolutionary ancestors, allowing them engage in certain complex behaviors, and to solve certain problems. At the same time, it also seems like we can conceive of a being that solved problems and behaved just like us without consciousness. Which of these intuitions should be rejected?

 I think the right move is to challenge the idea that zombies are actually conceivable. The philosopher Robert Kirk argues that the zombie argument commits, what he calls, the “jacket fallacy” (Kirk 2007). Imagine watching an infomercial about an extra lightweight winter jacket. The jacket is described as paper thin, contains one layer of material, and weights only a couple of ounces. Given that most winter jackets tend to be thick, well-insulated, and heavy, one may be rightfully skeptical that the extra lightweight winter jacket will work as advertised. In fact, it seems like the typical features of a winter jacket (thickness, heaviness etc.) are what enable the user to keep warm. A winter jacket without any of the thermal properties would not be able to carry out the function of keeping someone warm. Likewise, having a human without its conscious mental properties may not be able to behave and act like a human with consciousness. The assumption that there could be a zombie actually begs the question against the physicalist. The physicalist would insist that consciousness is like the thermal properties of a winter jacket, in that, it is not something that can be eliminated without some other properties being stripped away as well.

What are we to say to the dualist who insists that we can conceive of zombies? I would say that it’s possible to be wrong about what one is conceiving. There are a number of instances—well known to philosophers of language—where our imaginative faculties are led astray. Not knowing that Superman and Clark Kent are one and the same individual, one may falsely believe that it is conceivable that Superman could be dead while Clark Kent is still alive. Given that they are the same person, the death of Superman would necessarily entail the death of Clark Kent. Because we may be ignorant of certain facts, it is possible for us to believe that something is conceivable when it is in fact not. If certain physicalist theories are correct (e.g. mind-brain identity theory) it would not be possible for us to conceive of a mind existing without a brain or body.

Given that we have grounds for thinking that the zombie argument might be fallacious, I do not find it to be a compelling objection to physicalism or monist theories of mind. Nonetheless, I think there are better arguments against physicalism that deserve serious attention (e.g. the knowledge argument). In a future post, I will discuss some of these arguments and offer some of the physicalist responses that I find most plausible.

Works cited:

Chalmers, D. J. (1996). The conscious mind: In search of a fundamental theory. Oxford University Press.
Kirk, R. (2007). Zombies and consciousness. Oxford University Press.

Seth, A. K. (2009). Functions of consciousness. Encyclopedia of consciousness, 1, 279-293.