Mind: multi-disciplinary

The Spanish histologist, onetime bodybuilder, selfie pioneer, and Nobel laureate Santiago Ramón y Cajal (May 1, 1852–October 17, 1934), widely considered the founding father of modern neuroscience, used drawing the way Dr. Sacks used writing — as a vital way of thinking out loud, of giving form to ideas, of making arguments and fleshing out theories around the skeleton of observations.

Cajal —who, given the magnitude of his contributions, ought to be as much of a household name as Darwin and Pasteur —created hundreds of exquisite, exceptionally skilled drawings to illustrate his scientific papers. 

In them, he laid out the basic architecture of the nervous system and tackled the grand unanswered question of his era: How do nerve impulses travel between separate cells, or, what is the neurological basis of reflexes? 

Art became the sandbox for testing his theories, which in turn became a centerpiece of modern science.