Stephen Hawking

If we want to travel into the future, we just need to go fast. Really fast. And I think the only way we're ever likely to do that is by going into space.

Before 1915, space and time were thought of as a fixed arena in which events took place, but which was not affected by what happened in it. Space and time are now dynamic quantities... space and time not only affect but are also affected by everything that happens in the universe.

I don't think the human race will survive the next thousand years, unless we spread into space.

Time travel used to be thought of as just science fiction, but Einstein's general theory of relativity allows for the possibility that we could warp space-time so much that you could go off in a rocket and return before you set out.

Life on Earth is at the ever-increasing risk of being wiped out by a disaster, such as sudden global nuclear war, a genetically engineered virus or other dangers we have not yet thought of.

We lived in a tall, narrow Victorian house, which my parents had bought very cheaply during the war, when everyone thought London was going to be bombed flat. In fact, a V-2 rocket landed a few houses away from ours. I was away with my mother and sister at the time, but my father was in the house.

Among physicists, I'm respected I hope.

When one's expectations are reduced to zero one really appreciates everything one does have.

My expectations were reduced to zero when I was 21. Everything since then has been a bonus.", December 12, 2004)]

I have noticed that even those who assert that everything is predestined and that we can change nothing about it still look both ways before they cross the street

I think computer viruses should count as life ... I think it says something about human nature that the only form of life we have created so far is purely destructive. We've created life in our own image.

I like physics, but I love cartoons.

Yet if there really were a complete unified theory, it would also presumably determine our actions__o the theory itself would determine the outcome of our search for it! And why should it determine that we come to the right conclusions from the evidence? Might it not equally well determine that we draw the wrong conclusion? Or no conclusion at all?

There should be no boundary to human endeavor.

Time and space are finite in extent, but they don't have any boundary or edge. They would be like the surface of the earth, but with two more dimensions.

God abhors a naked singularity.

Keeping an active mind has been vital to my survival, as has been maintaining a sense of humor.

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