You never change things by fighting the existing reality. To change something, build a new model that makes the existing model obsolete.

Dwell not too long upon sports: for as they refresh a man that is weary, so they weary a man that is refreshed.

Most of my advances were by mistake. You uncover what is when you get rid of what isn't.

By and large, I seem to have made more mistakes than any others of whom I know, but have learned thereby to make ever swifter acknowledgment of the errors and thereafter immediately set about to deal more effectively with the truths disclosed by the acknowledgment of erroneous assumptions.

Search others for their virtue, and yourself for your vices.

It is one of the strange facts of experience that when we try to think about the future, our thoughts jump backwards. It may well be that nature has some fundamental metaphysical law by which opening up what we call the future also opens up the past in equal degree.

Conceptuality is subjective; realization is objective.