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This month, we talk computers, brains, and minds with Jeff Buechner, Permanent Lecturer in Philosophy at Rutgers University, Newark. Click here to listen to our conversation.

Back in the 50s and 60s, a lot of philosophers were attracted to the idea that the human mind is basically a computer. Why would they find that idea attractive? Well, there was some excitement about the idea because it allowed us to characterize human minds not in terms of the stuff they’re made of (neurons, cells, brains, and so on), but in terms of what they do. Back when we were inclined to characterize human minds in terms of brains, we found it difficult to explain how e.g. I and my dog could both experience the same emotions, like fear or excitement. After all, we have totally different brains. But it seems comparably straightforward to say what a computer does in a way that abstracts over these distinctions: namely, it performs calculations. Think of a function as a rule that tells you how to transform an input into an output. In that case, you can think of what a computer does as computing the values of certain functions. For example, if you feed an adding machine the values 2 and 5, then it computes the value of the sum function for those two values, giving you 7. Thus, philosophers started calling the idea that minds are computers functionalism: if indeed the two are deeply similar, then maybe our minds are nothing more than mechanisms that compute certain functions.

This month, Jeff Buechner discusses an interesting objection to the idea that the mind is a computer, which was put forth by Saul Kripke in the 1970s. The basis of the objection is that in order to figure out which functions any particular machine is computing, we have to sneak a distinction between the machine functioning properly and malfunctioning through the back door. We can’t define which function a computer is computing just by looking at which values it actually produces; we have to look at which values it should produce if it’s working correctly. But if that’s the case, then we aren’t taking this difficult-to-explain phenomenon–the human mind–and explaining it in terms of something similar. Rather, we’re explaining it in terms of something that’s difficult to explain in exactly the same way: what it means to correctly follow a rule.

Tune in to hear our guest walk us through some fascinating philosophical territory on what it means to think!

Matt Teichman