90% of the mass in your body comes from empty space.

Occam's razor suggests that, if some event is physically plausible, we don't need recourse to more extraordinary claims for its being. Surely the requirement of an all-powerful deity who somehow exists outside of our universe, or multiverse, while at the same time governing what goes on inside it, is one such claim. It should thus be a claim of last, rather than first, resort.

In 5 billion years, the expansion of the universe will have progressed to the point where all other galaxies will have receded beyond detection.

I cannot stress often enough that what science is all about is not proving things to be true but proving them to be false.

Metaphysical speculation is independent of the physical validity of the Big Bang itself and is irrelevant to our understanding of it.

Science has been effective at furthering our understanding of nature because the scientific ethos is based on three key principles: (1) follow the evidence wherever it leads; (2) if one has a theory, one needs to be willing to try to prove it wrong as much as one tries to prove that it is right; (3) the ultimate arbiter of truth is experiment, not the comfort one derives from one's a priori beliefs, nor the beauty or elegance one ascribes to one's theoretical models.

The root cause of the looming energy problem - and the key to easing environmental, economic and religious tensions while improving public health - is to address the unending, and unequal, growth of the human population. And the one proven way to reduce fertility rates is to empower young women by educating them.