Why your brain could be made of Swiss cheese and it wouldn’t matter.
Surely the title is a joke? Well, yes and no. Of course, it matters that the brain you have right now is not made of Swiss cheese. However, what I want to point out is that it is possible in principle that something like your mind could be made entirely of Swiss cheese and, given the correct functional organisation, it wouldn’t matter. But to make this point we’ll have to go on a journey through behaviourism and functionalism in the philosophy of mind.
Functionalism is one of the most popular theoretical frameworks in the philosophy of mind. Briefly, functionalists claim that what determines mental states is not their internal constitution, but rather the role (or function) that they play in the system of which they are a part (Levin, 2018). For example, the state of “being worried” is defined not only by how it is related to various stimuli (or “inputs”), such as late-stage capitalism, impending economic collapse, etc., and responses (or “outputs”), such as posting memes about the aforementioned, but also by other mental states. These other mental states could be the belief that you are worried, your desire to get rid of your worry, and your memory of being worried last week, and knowing that what saved you then was a copious consumption of Marxist memes lamenting structural inequality. In other words, functionalism stresses the importance of how mental states are not simply related to sensory inputs and motor outputs, but also other mental states (Bailey 2014: 149).
But what is so good about functionalism? To see functionalism’s appeal, we have to first understand how it relates to another major theory of mind: behaviourism. Behaviourism is the doctrine that mental states are nothing more than behaviours or dispositions to act. To a behaviourist, therefore, to speak of relationships between mental states is simply to speak of the relationship between various forms of behaviour. They insist that any investigation into psychological states be answered on only behavioural terms, and that there is no difference between two different mental states unless there is a difference in the associated behaviour with each. Mental states, on this account, are understandable without reference to anything inside the behaving subject’s head. To be in pain is simply to gesticulate in such a way that signals pain, as opposed to, say, remorse.
Now, if this seems counterintuitive, you’re not alone. How could something we call a mental state be defined without reference to anything mental at all?! Well, the first issue the behaviourists were trying to avoid was the fact that introspective access to what we normally call our mental states is superbly adept at leading us astray (hallucinations being an easy example).
Secondly, they claimed that if we want a science of the mind, then the contents of such a science should be amenable to third party verification and observation. Mental states do not seem like the kind of thing that we could put to this kind of test: I cannot cut open your cranium and see the mental state that corresponds to you being in pain. I might be able to put you into a scanner and read off various data which correspond to you being in pain, but the physical events in your head and the mental event of you being in pain are very different. The mental state is something you report (i.e. subjective), whereas the evidence from the scanner is accessible to other observers (i.e. objective). Behaviourists claim we cannot rely on such introspective accounts in our analysis of the mental. As Gilbert Ryle put it: “the sorts of things I can find out about myself are the same as the sorts of things I can find out about other people, and the methods of finding them out are much the same” (Bailey 2014: 98). So behaviourists thought they were being very scientific. But were they?
Let’s go back to the example of pain (a favourite among philosophers, perhaps because we’re all sadists?). Now, the behaviourists want to claim that the mental state of being in pain is just those external cues we associate with pain. An issue that immediately presents itself is that if mental states are just behaviours, then mental states do not cause behaviours. This is because mental states and behaviours are the same thing: they are effects, or responses to various forms of stimuli, not the cause thereof. To put it simply: things cannot cause themselves (unless you’re a god, in which case you probably don’t exist…)
So, our mental states do not cause our behaviour, leaving us inert and seemingly incapable of meaningful action. If there is one thing most people believe about themselves it is that the thoughts in their heads play some kind of role in their eventual behaviour. Moreover, it seems that effects of pain states are not just linked to various gesticulations: there may be attendant beliefs at play while one is in pain, such as the belief that a doctor should be called, the desire to be rid of the pain, or that punching fascists will relieve the pain. Such internal states cannot be captured at all by simply referring to behaviour.
This, then, is how we might find ourselves endorsing functionalism: recall that functionalism claims that mental states are related to stimulus inputs and behavioural outputs, but that they are also related to other mental states. This then seems to solve the problem of behaviourism mentioned above: we can now claim that, yes, being in pain may involve all kinds of gesticulations, but it can also consist of various beliefs and desires. Moreover, this account also has a place for the fact that there is something it is like to be in pain, which the strictly behavioural account seemed to miss. On this functional understanding, mental states come to be defined by the functional roles that they play.
A “functional role” here refers not to any particular substance, but rather to an abstraction, a role in a particular system. For example, the function of the heart is to pump blood around the body. Now, it just so happens that we humans have hearts made out of biological materials, but it would make no difference if this biological heart were to be replaced by an artificial heart that performed the same function or played the same functional role as its biological counterpart. In this way functionalism is substrate neutral: what matters is not whether the heart is made of silicon or living cells, but simply that it pumps blood. So long as this artificial “heart” is pumping blood around the body, it will do.
What does any of this have to do with your brain being made of appropriately organised Emmental? Well, if being in a particular mental state refers to the functional role that the mental state plays, then, as we have seen, it does not matter what substrate the mental state happens to be realised in. The collection of mental states that is your mind is not necessarily determined by the fact that your mind, at the moment at least, happens to be realised in some wetware. Should a similar organisation of matter come to be instantiated in various kinds of dairy products, stones, etc. we should then concede that this would indeed constitute a kind of mind. A sufficiently complex collection of Swiss cheese (however unlikely this scenario is to arise) may just be capable of doing the job. We should not mistake a failure of imagination for an insight into necessity (Dennett, 1991).This is not an argument for veganism, but perhaps think carefully before your next cheeseboard (over)indulgence.
References
Bailey, A. (ed.) (2014) Philosophy of Mind. London: Bloomsbury.
Dennett, D. C. (1991) Consciousness Explained. New York: Black Bay Books.
Levin, J. (2018) Functionalism. Fall 2018. Edited by E. N. Zalta. The Stanford Encyclopedia of Philosophy. Available at: https://plato.stanford.edu/archives/fall2018/entries/functionalism/.
