“Only two things are infinite, the universe and human stupidity, and I’m not sure about the former”

“You do not really understand something unless you can explain it to your grandmother”

“Common sense is the collection of prejudices acquired by age 18”

“Passion very often makes the wisest men fools, and very often too inspires the greatest fools with wit”

“It is impossible to love and to be wise”

“A wise man sees as much as he ought, not as much as he can”