A fool is someone whose pencil wears out before its eraser does.

Geometry is beautifully logical, and it teaches you how to think and prove that things are so, step by step by step. Proofs are excellent lessons in reasoning. Without logic and reasoning, you are dependent on jumping to conclusions or - worse - having empty opinions.

People who work crossword puzzles know that if they stop making progress, they should put the puzzle down for a while.

Ultimately, our future is like a mirror. Whenever we face it, it always reflects what we left behind.

Be able to recognize the dangerous snakes, spiders, insects, and plants that live in your area of the country.

Feeling is what you get for thinking the way you do.

Think of a hypothesis as a card. A theory is a house made of hypotheses.