We are in danger of destroying ourselves by our greed and stupidity. We cannot remain looking inwards at ourselves on a small and increasingly polluted and overcrowded planet.

The beatings will continue until morale improves.

Mankind's greatest achievements have come about by talking and its greatest failures by not talking. It doesn’t have to be like this.

I want my books sold on airport bookstalls.

Many badly needed goals, like fusion and cancer cure, would be achieved much sooner if we invested more.

I believe in the possible. I believe, small though we are, insignificant though we may be, we can reach a full understanding of the universe. You were right when you said you felt small, looking up at all that up there. We are very, very small, but we are profoundly capable of very, very big things.

When two's company, three's the result!