In Crime and Punishment Part 5, Chapter 5, Lebeziatnikov tells Raskolnikov about a professor in Paris who believed in curing the insane through the...

Here's the passage from the novel in question; as you can see, the characters never mention a specific psychologist's name:

"Excuse me, excuse me; of course it would be rather difficult for Katerina Ivanovna to understand, but do you know that in Paris they have been conducting serious experiments as to the possibility of curing the insane, simply by logical argument? One professor there, a scientific man of standing, lately dead, believed in the possibility of such treatment. His idea was that there's nothing really wrong with the physical organism of the insane, and that insanity is, so to say, a logical mistake, an error of judgment, an incorrect view of things. He gradually showed the madman his error and, would you believe it, they say he was successful? But as he made use of douches too, how far success was due to that treatment remains uncertain.... So it seems at least."

Although we can't say for certain, Lebeziatnikov and Raskolnikov may have been discussing Philippe Pinel, a 19th-century French physician and psychiatrist who is well-known for advocating for more humane treatment of patients in insane asylums. We can thank him for helping people make that important shift from restraining and punishing the mentally ill to helping them and maintaining their dignity.

So you won't be surprised to know, also, that Pinel was known for using logic in his therapy sessions, helping his patients see that their delusions didn't make sense. The goal was to lead the patients back to a more sane understanding of reality. He believed that this kind of logical therapy should be the first line of defense against insanity, with medicines following afterward. It's a very modern idea: ask therapists today whether they agree with Pinel, and you'll probably find that they do.