Leonardo da Vinci:
Among the great things which are found among us, the existence of Nothing is the greatest.
Every part is disposed to unite with the whole, that it may thereby escape from its own incompleteness.
The noblest pleasure is the joy of understanding.
Where there is shouting, there is no true knowledge.
The earth is moved from its position by the weight of a tiny bird resting upon it.
The smallest feline is a masterpiece.
Simplicity is the ultimate sophistication.
Anyone who conducts an argument by appealing to authority is not using his intelligence; he is just using his memory.
Iron rusts from disuse; water loses its purity from stagnation… even so does inaction sap the vigor of the mind.
Everything comes from everything, and everything is made out of everything, and everything returns into everything…
There are three classes of people: those who see, those who see when they are shown, those who do not see.