Many people are unhappy because there was some point in their past where there was some glory day, and as they get older they're not creating more glory days. They reflect on a time that they will never reach again, and it brings some level of dissatisfaction into their lives. I have circumvented that by simply making incumbent upon myself to always be productive in ways that are consistent with my physical body, my mental state of knowledge, but more important, my presumed growth in wisdom that would come with age.

The show [ StarTalk ] was born as a radio program out of a National Science Foundation grant.

Once you've got the makings of a star, gravity draws leftover gas and dust into a giant swirling disk. The dust continues to stick together, clumping into rocky asteroids, which eventually become orbiting rocky planets. And voila: a solar system!

If you are that person, you are more likely to believe that God cured you, this invisible force, creator of the universe, cured you, than that you had three idiotic doctors diagnose you. ... I taught physics to pre-med students who became doctors. Not all of them are smart, I assure you.

The typical person has no trouble believing without knowing. What people need to realize is simply that you do not need to believe to know.

This fear factor, this war driver is a very strong one and it's been with the species ever since the beginning and it motivated the Great Wall of China. War can be aggressive or defensive, right? So it motivated the Great Wall of China. Our space program was reactive to Russia.

There are no wild, seedless watermelons. There's no wild cows... You list all the fruit, and all the vegetables, and ask yourself, is there a wild counterpart to this? If there is, it's not as large, it's not as sweet, it's not as juicy, and it has way more seeds in it. We have systematically genetically modified all the foods, the vegetables and animals that we have eaten ever since we cultivated them. It's called artificial selection.