"Nothing exists except atoms and empty space. Everything else is opinion. "
"Judge a man by his questions, not by his answers."
"Any fool can know. The point is to understand."
"It is the mark of an educated man to be able to entertain a thought without accepting it"
"The unexamined life is not worth living"
"I would rather have questions that can't be answered than answers that can't be questioned"
"I learned very early the difference between knowing the name of something and knowing something."
"The pleasure of finding things out."
"We are what we repeatedly do. Excellence, then, is not an act, but a habit"
"Don't you have time to think?"
"Opinion is the medium between knowledge and ignorance"
"The roots of education are bitter, but the fruit is sweet"
"It's not that I am so smart. But I stay with the questions much longer."
"The first principle is that you must not fool yourself. And you are the easiest person to fool. "
"We cannot solve our problems with the same thinking we used when we created them."
"I would trade all my technology for an afternoon with Socrates"