Only a few centuries ago, a mere second in cosmic time, we knew nothing of where or when we were. Oblivious to the rest of the cosmos, we inhabited a kind of prison, a tiny universe bounded by a nutshell.

How did we escape from the prison? It was the work of generations of searchers who took five simple rules to heart.

(1) Question authority. No idea is true just because someone says so, including me.

(2) Think for yourself. Question yourself. Don’t believe anything just because you want to. Believing something doesn’t make it so.

(3) Test ideas by the evidence gained from observation and experiment. If a favorite idea fails a well-designed test, it’s wrong. Get over it.

(4) Follow the evidence wherever it leads. If you have no evidence, reserve judgment.

And perhaps the most important rule of all…

(5) Remember: you could be wrong. Even the best scientists have been wrong about some things. Newton, Einstein, and every other great scientist in history — they all made mistakes. Of course they did. They were human.

Science is a way to keep from fooling ourselves, and each other.

Only a few centuries ago, a mere second in cosmic time, we knew nothing of where or when we were. Oblivious to the rest of the cosmos, we inhabited a kind of prison, a tiny universe bounded by a nutshell.

Neil deGrasse Tyson

A quote from the final episode of Cosmos: A Spacetime Odyssey which was very humbling and inspirational.