Mental illness has been in the headlines a lot recently. But what is it really? Guests Dr. Allan H. Ropper and Brian David Burrell are authors of the brand new book How The Brain Lost Its Mind, which takes a look at the strange history of two misunderstood ailments: syphilis and hysteria, and the efforts to confront their effects on mental life. How does the mind work? Where does mental illness lie, in the brain or in the mind? And how should it be treated?