If you are only skeptical, then no new ideas make it through to you. You become a crotchety old person convinced that nonsense is ruling the world. (There is, of course, much data to support you.) But every now and then, a new idea turns out to be on the mark, valid and wonderful. If you are too much in the habit of being skeptical about everything, you are going to miss or resent it, and either way you will be standing in the way of understanding and progress.

But down deep, at the molecular heart of life we're essentially identical to trees.

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

The claim is also sometimes made that science is as arbitrary or irrational as all other claims to knowledge, or that reason itself is an illusion. As Ethan Allen said Those who invalidate reason ought seriously to consider whether they argue against reason with or without reason; if with reason, then they establish the principle that they are labouring to dethrone. If they argue without reason, which they must do, in order to be consistent with themselves, they are out of reach of rational conviction, nor do they deserve a rational argument.

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.

At the heart of science is an essential balance between two seemingly contradictory attitudes-an openness to new ideas, no matter how bizarre or counterintuitive they may be, and the most ruthless skeptical scrutiny of all ideas, old and new. This is how deep truths are winnowed from deep nonsense.

It would be wryly interesting if in human history the cultivation of marijuana led generally to the invention of agriculture, and thereby to civilization.