One of the evident facts about the world is the stability of empty space-time. In classical general relativity we can explain this as a consequence of the positive energy theorem... the positive energy theorem must extend in some suitable form to any viable quantum theory of gravity.
Lee SmolinRelated topics
classical empty form general quantum relativity stability theorem viable facts space-timeRelated quotes
We must consider not only why the classical theory of democracy appears to be in contradiction with the observed practice, but also why the many different responses to this observation, though mutually incompatible, all share the belief that democracy is the best form of political organization.
Moses I. Finley
It is essential to grasp the incontestable truth that a Marxist must take cognisance of real life, of the true facts of reality, and not cling to a theory of yesterday, which, like all theories, at best only outlines the main and the general, only comes near to embracing life in all its complexity.
Vladimir Lenin
The usefulness of observation and measurement in testing economic theories arises because the theorems of economics are supposed to relate to the actual world... Any economic theorem rigorously deduced from given postulates may be regarded as a hypothesis about the actual world which xperience may show to be false.
Richard Stone
I have this theory about words: There's a thousand ways to say "Pass the salt." It could mean, you know, "Can I have some salt?" or it could mean, "I love you." It could mean "I'm very annoyed with you" – really, the list could go on and on. Words are little bombs, and they have a lot of energy inside them.
Christopher Walken