The great questions are those an intelligent child asks and, getting no answers, stops asking.

There's life all over this universe, but the only life in the solar system is on earth, and in the whole universe we are the only men.

So-called defense now absorbs sixty per cent of the national budget, and about twelve per cent of the Gross National Product.

The great questions are those an intelligent child asks and, getting no answers, stops asking.

We are living in a world in which all wars are wars of defense.

A scientist is in a sense a learned small boy. There is something of the scientist in every small boy. Others must outgrow it. Scientists can stay that way all their lives.

I can conceive of no nightmare so terrifying as establishing communication with a so-called superior (or, if you wish, advanced) technology in outer space.