As every divided kingdom falls, so every mind divided between many studies confounds and saps itself.
Leonardo da VinciThe acquisition of knowledge is always of use to the intellect, because it may thus drive out useless things and retain the good. For nothing can be loved or hated unless it is first known.
Leonardo da VinciA good memory, which nature has endowed us with, causes things long past to seem present.
Leonardo da VinciO time, swift robber of all created things, how many kings, how many nations hast thou undone, and how many changes of states and of various events have happened since the wondrous forms of this fish perished here in this cavernous and winding recess. Now destroyed by time thou liest patiently in this confined space with bones stripped and bare; serving as a support and prop for the superimposed mountain.
Leonardo da VinciAs regards this vice, we read that the peacock is more guilty of it than any other animal. For it is always contemplating the beauty of its tail, which it spreads in the form of a wheel, and by its cries attracts to itself the gaze of the creatures that surround it. And this is the last vice to be conquered.
Leonardo da Vinci