Behaviourists take the view that mental states are essentially behavioural: to be in pain, for example, is just to behave, or be disposed to behave, in certain ways (to writhe and go ‘Ow!’, and so on). Behavourism, if true, would neatly explain how mind and body are related. Minds are not queer, ethereal entities that exist in addition to our physical bodies, and that are hidden behind our behaviour. Rather, to have a mind just is to be disposed to behave in certain ways, and that is something even a physical object can be. Nowadays behaviourism, as a philosophy of mind, is philosophically out of fashion. But here, Rowland Stout explains why he still believes it may be true.