Socrates:

Socrates was an Ancient Greek philosopher and scientist. Many consider him one of the wisest men to have ether existed. He also said: "I am the wisest man alive, for I know one thing, and that is that I know nothing."  and "I know nothing except the fact of my ignorance", showing he believed that there is a lot to learn, and that we should realize we know nothing in comparison with the size of the universe.