Details make perfection, and perfection is not a detail.
Necessity is a guardian in Nature.
The deeper the feeling, the greater the pain
If a man has a tent made of linen of which the apertures have all been stopped up, and be it twelve bracchia across (over twenty-five feet) and twelve in depth, he will be able to throw himself down from any height without sustaining injury. [His concept of the parachute.]
The Medici made me and the Medici destroyed me.
Every action needs to be prompted by a motive. To know and to will are two operations of the human mind. Discerning, judging, deliberating are acts of the human mind.