Quote by Galileo Galilei
"One cannot teach what one does not know."
More from Galileo Galilei
"In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual."
"All truths are easy to understand once they are discovered; the point is to discover them."
"We cannot teach people anything; we can only help them discover it within themselves."
"Mathematics is the language in which God has written the universe."