He 'profited by' his experience/mistake. [=he learned something useful from his experience/mistake]
The book can be read with 'profit' by anyone who wants to understand how the system works.
We sold the house 'at a profit'. [=we made a profit when we sold our house]
(..) - It becomes instinct. I observe that you, in one respect, are very fortunate. I'll make one suggestion. Why, I do not know. It cannot possibly profit me. Have you heard about the letters of transit? Yes, something. They were not found on Ugarte when they arrested him. (..)1942 Casablanca