Plato is my friend — Aristotle is my friend — but truth is a greater friend.
If I have seen further it is by standing on ye sholders of Giants.
I have not been able to discover the cause of those properties of gravity from phenomena, and I frame no hypotheses; for whatever is not deduced from the phenomena is to be called a hypothesis, and hypotheses, whether metaphysical or physical, whether of occult qualities or mechanical, have no place in experimental philosophy.
People often say that I'm curious about too many things at once. But can you really forbid a man from harboring a desire to know and embrace everything that surrounds him?
We shall not cease from exploration, and the end of all our exploring will be to arrive where we started and know the place for the first time.
To study the meaning of man and of life — I am making significant progress here. I have faith in myself. Man is a mystery: if you spend your entire life trying to puzzle it out, then do not say that you have wasted your time. I occupy myself with this mystery, because I want to be a man.