Our educational system is like an automobile which has strong rear lights, brightly illuminating the past. But looking forward things are barely discernible.

The rockets… can be built so powerfully that they could be capable of carrying a man aloft.

To make available for life every place where life is possible. To make inhabitable all worlds as yet uninhabitable, and all life purposeful.

I refrained from writing another one, thinking to myself: Never mind, I will prove that I am able to become a greater scientist than some of you, even without the title of doctor.

If there is a small rocket on top of a big one, and if the big one is jettisoned and the small one is ignited, then their speeds are added.

In the United States, I am often addressed as a doctor. I should like to point out, however, that I am not such and shall never think of becoming one.