Reason requires a body to do its thinking.

 Reason is not disembodied, as the tradition has largely held, but arises from the nature of our brains, bodies, and bodily experience.

This is not just the innocuous and obvious claim that we need a body to reason; rather, it is the striking claim that the very structure of reason itself comes from the details of our embodiment.

The same neural and cognitive mechanisms that allow us to perceive and move around also create our conceptual systems and modes of reason.

Thus, to understand reason we must understand the details of our visual system, our motor system, and the general mechanisms of neural binding.

In summary, reason is not, in any way, a transcendent feature of the universe or of disembodied mind. Instead, it is shaped crucially by the peculiarities of our human bodies, by the remarkable details of the neural structure of our brains, and by the specifics of our everyday functioning in the world.

 Reason is evolutionary, in that abstract reason builds on and makes use of forms of perceptual and motor inference present in "lower" animals. The result is a Darwinism of reason, a rational Darwinism: Reason, even in its most abstract form, makes use of, rather than transcends, our animal nature.

The discovery that reason is evolutionary utterly changes our relation to other animals and changes our conception of human beings as uniquely rational. Reason is thus not an essence that separates us from other animals; rather, it places us on a continuum with them.