A reader writes:

Grayling is very correct, but neglects to mention that even the physical component of the mind is not restricted to the brain. Hormones play a huge role in how we feel, as well as are vastly influential in how we process information. I would argue that the mind does not physically reside in that spot behind the eyes, but it is merely concentrated there. There are diffuse components throughout; feeling something in your gut, loins, or heart aren't merely figures of speech. Ask a post-operative transgendered individual whether the new reproductive organs and hormone therapy are a part of a change in thought, or an ophidiophobe whether adrenal glands matter to logic and reason when a snake is encountered.

Minds are a diffuse thing, most heavily concentrated in our brains, but with diffuse components that extend throughout our bodies, into our friends and neighbors, into our libraries and interwebs, and even into pets and inanimate objects. They are like gravity wells, where the lines are blurred and matter (or thought in this case) is largely considered to be in one well, but is really influenced by many at once.

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