"The history of ideas is the history of the grudges of solitary men."

"To explain the unknown by the known is a logical procedure; to explain the known by the unknown is a form of theological lunacy."

"We are kept keen on the grindstone of pain and necessity."

"Entia non sunt multiplicanda praeter necessitatem (Entities must not be multiplied beyond necessity.)"

"It is astonishing with how little wisdom mankind can be governed, when that little wisdom is its own."

"Nothing in the world is as certain as death."

"The aim of every artist is to arrest motion, which is life, by artificial means and hold it fixed so that a hundred years later, when a stranger looks at it, it moves again since it is life."

"The squeaking wheel doesn't always get the grease. Sometimes it gets replaced."

"Quality is never an accident; it is always the result of high intention, sincere effort, intelligent direction and skillful execution; it represents the wise choice of many alternatives."

"When we are angry or depressed in our creativity, we have misplaced our power. We have allowed someone else to determine our worth, and then we are angry at being undervalued."

"People are like stained glass windows; they sparkle and shine when the sun is out, but when the darkness sets in, their true beauty is revealed only if there is light within."

"Nature abhors a vacuum. When a head lacks brains, nature fills it with conceit."