While travelling, Leonardo kept a small notebook at the ready for notes and sketching. In one of these notebooks, he listed a number of things he wished to accomplish in one week or month in the late 1490s.

What a jumble! Cannons, wall construction, studying the sun, ice skating in Flanders, optics, and that oh-so-casual, “Draw Milan.” It’s like his mind could wander off in any direction at any time. How did he concentrate? How did he focus?

Maybe he went in and out, plunging into a task that concentrated him fully, and then, once done, he’d spring back to the rough and tumble of Anything Goes. Great minds can go as they please.

Another giant, Michel Montaigne, the inventor of the essay, wrote that no single idea could hold him. “I cannot keep my subject still,” he wrote. “It goes along, befuddled and staggering, with a natural drunkenness.”

I like being drunk like that.