The Book of French Mathematician Jacques Hadamard


The Psychology of Invention in the Mathematical Field. 

https://www.amazon.fr/Psychology-Invention-Mathematical-Field/dp/0486201074


The book discusses the four stages of thought : 

1); Preparation (conscious work setting up the problem and trying to solve it)

2); incubation (no conscious work on the problem)

3); illumination (the fruits of incubation where an insight is received) and finally 

4): verification (consciously testing and verifying the insight)


Gromov's Ergobrain Program for Universal learning program

Great Circle of Mysteries
Mathematics, the World, the Mind
Authors: Gromov, M.

https://www.springer.com/gp/book/9783319530482#:~:text=This%20visionary%20and%20engaging%20book,the%20brain%20and%20the%20mind.&text=It%20argues%20that%20the%20core,mathematical%20context%20for%20its%20understanding.