To me, the most compelling telling of the Grothendeick story is this:
https://www.psychologytoday.com/us/articles/201707/the-mad-g...
A different telling of another profoundly gifted character is this:
http://www.inquiriesjournal.com/articles/1638/divinity-in-th...
The state of mind where new ideas are born is a liminal state that integrates disciplines effortlessly. Think Herb Simon, Marshall McLuhan or Arthur Koestler.