The Apollo pictures of the whole Earth conveyed to multitudes something well known to astronomers: On the scale of the worlds - to say nothing of stars or galaxies - humans are inconsequential, a thin film of life on an obscure and solitary lump of rock and metal

The very act of understanding is a celebration of joining, merging, even if on a very modest scale, with the magnificence of the Cosmos.

Recent research shows that many children without enough to eat wind up with diminished capacity to understand and learn (“cognitive impairment” ). Children don't have to be starving for this to happen. Even mild undernourishment — the kind most common among poor people in America — can do it.

The total number of stars in the Universe is larger than all the grains of sand on all the beaches of the planet Earth.

Chlorine is a deadly poison gas employed on European battlefields in World War I. Sodium is a corrosive metal which burns upon contact with water. Together they make a placid and unpoisonous material, table salt. Why each of these substances has the properties it does is a subject called chemistry.

Not all birds can fly. What separates the flyers from the walkers is the ability to take off.

One of the saddest lessons of history is this: If we’ve been bamboozled long enough, we tend to reject any evidence of the bamboozle. We’re no longer interested in finding out the truth. The bamboozle has captured us. It’s simply too painful to acknowledge, even to ourselves, that we’ve been taken. Once you give a charlatan power over you, you almost never get it back.