[T]he real world out there … must exist independently of us.

… the greatest heroes in the history of science…. No one in human history has ever guessed correctly about such a large expansion of the known world.

[S]upersymmetric string theories are deeply elegant objects.

… in loop quantum gravity appeared to contradict Einstein’s special theory. … [T]hat possibility was too scary to contemplate, and after struggling with this, I dropped the whole line of research.

There is no way we can have two theories of nature covering different phenomena, as if one had nothing to do with the other. Any claim for a final theory must be a complete theory of nature. It must encompass all we know.

Don’t start with space or anything moving in space. Start with something that is purely quantum mechanical and has, instead of space, some kind of purely quantum structure.

The search for quantum gravity is a true quest.

We need a theory about what makes up space, a background-independent theory.

More and more, I have the feeling that quantum theory and general relativity are both deeply wrong about the nature of time.