The truly privileged theories are not the ones referring to any particular scale of size or complexity, nor the ones situated at any particular level of the predictive hierarchy - but the ones that contain the deepest explanations.

The overwhelming majority of theories are rejected because they contain bad explanations, not because they fail experimental tests.

Feeling insignificant because the universe is large has exactly the same logic as feeling inadequate for not being a cow.

To me quantum computation is a new and deeper and better way to understand the laws of physics, and hence understanding physical reality as a whole.

Like every other destruction of optimism, whether in a whole civilisation or in a single individual, these must have been unspeakable catastrophes for those who had dared to expect progress. But we should feel more than sympathy for those people. We should take it personally. For if any of those earlier experiments in optimism had succeeded, our species would be exploring the stars by now, and you and I would be immortal.

Every problem that is interesting is also soluble.

Discovering a new explanation is inherently an act of creativity.