Looking back at the worst times, it always seems that they were times in which there were people who believed with absolute faith and absolute dogmatism in something. And they were so serious in this matter that they insisted that the rest of the world agree with them. And then they would do things that were directly inconsistent with their own beliefs in order to maintain that what they said was true.

If you know that you are not sure, you have a chance to improve the situation. I want to demand this freedom for future generations.

I have the advantage of having found out how hard it is to get to really know something. How careful you have to be about checking your experiments. How easy it is to make mistakes and fool yourself. I know what it means to know something.

It turns out that all life is interconnected with all other life.

We've learned from experience that the truth will out.

To not know math is a severe limitation to understanding the world.

When a scientist doesn't know the answer to a problem, he is ignorant. When he has a hunch as to what the result is, he is uncertain. And when he is pretty darn sure of what the result is going to be, he is still in some doubt. We have found it of paramount importance that in order to progress we must recognize our ignorance and leave room for doubt. Scientific knowledge is a body of statements of varying degrees of certainty - some most unsure, some nearly sure, but none absolutely certain.