No theory changes what it is a theory about; man remains what he has always been.
Sentiment: NEGATIVE
Never abandon a theory that explains something until you have a theory that explains more.
I'm not sure what theory is, unless it's the pursuit of fundamental questions.
There is no complete theory of anything.
A young man is a theory, an old man is a fact.
Theories, for me, are just about freeing your mind. It doesn't mean the theory is going to work like a scientific theory works. It's about freeing your mind and making you think a different way.
A theory must be tempered with reality.
Theories come and go, but fundamental data always remain the same.
The standard theory may survive as a part of the ultimate theory, or it may turn out to be fundamentally wrong. In either case, it will have been an important way-station, and the next theory will have to be better.
Read no history: nothing but biography, for that is life without theory.
The state of the world, of course, is constantly changing, and so is theory.