More than any other Leonardo book I’ve read, this one helps you see him as a complete human being and understand just how special he was. He came close to understanding almost all of what was known on the planet at the time. That’s partly because scientific knowledge was relatively limited back then, partly because he had a high IQ, but mostly because he was insatiably curious about pretty much every area of natural science and the human experience. He studied, in meticulous detail, everything from the flow of water and the rise of smoke to the muscles you use when you smile.
Curiosity is king.