[Science] is not perfect. It can be misused. It is only a tool. But it is by far the best tool we have, self-correcting, ongoing, applicable to everything. It has two rules. First: there are no sacred truths; all assumptions must be critically examined; arguments from authority are worthless. Second: whatever is inconsistent with the facts must be discarded or revised. ... The obvious is sometimes false; the unexpected is sometimes true.

It means nothing to be open to a proposition we don't understand.

If we're capable of conjuring up terrifying monsters in childhood, why shouldn't some of us, at least on occasion, be able to fantasize something similar, something truly horrifying, a shared delusion, as adults?

Curiosity and the urge to solve problems are the emotional hallmarks of our species.

We are made of stellar ash. Our origin and evolution have been tied to distant cosmic events. The exploration of the cosmos is a voyage of self-discovery.

The prediction of nuclear winter is drawn not, of course, from any direct experience with the consequences of global nuclear war, but rather from an investigation of the governing physics.

If you want to make a [rhubarb] pie from scratch, first you have to create the universe.