Scientific truth is not what any one scientist puts forth. It can be that, but it is generally not. It is the sum of multiple studies that all lean in the same direction in their results conducted by different people at different times of different nationalities with different competitive urges who all end up getting the same result. Then you have an emerging scientific truth, and then you put that in the textbooks, and that will never be shown to be wrong later on.

We are star dust in the highest exalted way, called by the universe, reaching out to the universe

So much of what we understand comes from knowing what something is and what that something used to be, which allows us to figure out, or at least imagine, what happened in between.

As a scientist, I want to go to Mars and back to asteroids and the Moon because I'm a scientist. But I can tell you, I'm not so naive a scientist to think that the nation might not have geopolitical reasons for going into space.

My investment of time, as an educator, in my judgment, is best served teaching people how to think about the world around them. Teach them how to pose a question. How to judge whether one thing is true versus another.

Where did the concept of "without borders" come from? No one had that concept until you saw Earth from space, illustrated not by a mapmaker who's color-coding political boundaries; it's illustrated by nature itself and there's land, there's ocean, there's atmosphere.

Kids are born curious about the world. What adults primarily do in the presence of kids is unwittingly thwart the curiosity of children.