Conscious thought is the greatest hindrance to the proper execution of all physical action.
--Bruce Lee

As we know, there are known knowns. And there are things we know we know. We also know there are known unknowns. That is to say we know there are some things we do not know, but there are also unknown unknowns, the ones we don't know we don't know.
--Donald Rumsfeld, Secretary of Defense

They that can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety.
--Benjamin Franklin