What is necessary for 'the very existence of science,' and what the characteristics of nature are, are not to be determined by pompous preconditions, they are determined always by the material with which we work, by nature herself. We look, and we see what we find, and we cannot say ahead of time successfully what it is going to look like. ... It is necessary for the very existence of science that minds exist which do not allow that nature must satisfy some preconceived conditions.
Richard P. FeynmanThere is no harm in doubt and skepticism, for it is through these that new discoveries are made.
Richard P. FeynmanIt's because somebody knows something about it that we can't talk about physics. It's the things that nobody knows anything about we can discuss.
Richard P. Feynman