Why can't we summon the ingenuity and courage of the generations that came before us? The dinosaurs never saw that asteroid coming. What's our excuse?

I as an astrophysicist, see the universe, feel the universe, smell the universe every day. Every day. And for people to say, I'm cool, I'm right here, it's all I need.

Everyone should have their mind blown once a day.

We live in the kind of society where, in almost all cases, hard work is rewarded.

It seems that we're better at finding someone to blame for our problems than we are at finding creative solutions to fix them.

Everything we do understand about the universe - the periodic table of elements, Einstein's laws, Newton's laws, all of chemistry, all of biology - that's 4 percent of the universe. We got to the moon on the 4 percent we do understand. We landed on Mars on the 4 percent we do understand. So the day we crack the nut of the rest of that 95 percent... Oh my gosh.

A common way to compute density is, of course, to take the ratio of an object's mass to its volume. But other types of densities exist, such as the resistance of somebody's brain to the imparting of common sense.