Stephen Hawking Quotes

133 Sourced Quotes

We won't find anywhere as nice as Earth unless we go to another star system.
On colonizing space

Stephen Hawking
It is not clear that intelligence has any long-term survival value.

Stephen Hawking
So Einstein was wrong when he said, "God does not play dice." Consideration of black holes suggests, not only that God does play dice, but that he sometimes confuses us by throwing them where they can't be seen.

Stephen Hawking
Bodies like the earth are not made to move on curved orbits by a force called gravity; instead, they follow the nearest thing to a straight path in a curved space, which is called a geodesic. A geodesic is the shortest (or longest) path between two nearby points.

Stephen Hawking
As philosopher of science Karl Popper has emphasized, a good theory is characterized by the fact that it makes a number of predictions that could in principle be disproved or falsified by observation.

Stephen Hawking
I regard [the many worlds interpretation] as self-evidently correct. [T. F.: Yet some don't find it evident to themselves.] Yeah, well, there are some people who spend an awful lot of time talking about the interpretation of quantum mechanics. My attitude — I would paraphrase Goering—is that when I hear of Schrödinger's cat, I reach for my gun.

Stephen Hawking
We find ourselves in a bewildering world. We want to make sense of what we see around us and to ask: What is the nature of the universe? What is our place in it and where did it and we come from? Why is it the way it is?

Stephen Hawking
We are all different - but we share the same human spirit. Perhaps it's human nature that we adapt - and survive.

Stephen Hawking
Many people would claim that the boundary conditions are not part of physics but belong to metaphysics or religion. They would claim that nature had complete freedom to start the universe off any way it wanted. That may be so, but it could also have made it evolve in a completely arbitrary and random manner. Yet all the evidence is that it evolves in a regular way according to certain laws. It would therefore seem reasonable to suppose that there are also laws governing the boundary conditions.

Stephen Hawking
Science could predict that the universe must have had a beginning.

Stephen Hawking
Although I'm regarded as a dangerous radical by particle physicists for proposing that there may be loss of quantum coherence, I'm definitely a conservative compared to Roger. I take the positivist viewpoint that a physical theory is just a mathematical model and that it is meaningless to ask whether it corresponds to reality. All that one can ask is that its predictions should be in agreement with observation. I think Roger [Penrose] is a Platonist at heart but he must answer for himself.

Stephen Hawking
One could say: "The boundary condition of the universe is that it has no boundary." The universe would be completely self-contained and not affected by anything outside itself. It would neither be created nor destroyed. It would just BE.

Stephen Hawking
If aliens visit us, the outcome would be much as when Columbus landed in America, which didn't turn out well for the Native Americans. … We only have to look at ourselves to see how intelligent life might develop into something we wouldn't want to meet.

Stephen Hawking
I am discounting reports of UFOs. Why would they appear only to cranks and weirdos?

Stephen Hawking
What I have done is to show that it is possible for the way the universe began to be determined by the laws of science. In that case, it would not be necessary to appeal to God to decide how the universe began. This doesn't prove that there is no God, only that God is not necessary.

Stephen Hawking
Maybe that is our mistake: maybe there are no particle positions and velocities, but only waves. It is just that we try to fit the waves to our preconceived ideas of positions and velocities. The resulting mismatch is the cause of the apparent unpredictability.

Stephen Hawking
Although September 11 was horrible, it didn't threaten the survival of the human race, like nuclear weapons do.

Stephen Hawking
Most sets of values would give rise to universes that, although they might be very beautiful, would contain no one able to wonder at that beauty.

Stephen Hawking
Science predicts that many different kinds of universe will be spontaneously created out of nothing. It is a matter of chance which we are in.

Stephen Hawking
Each time new experiments are observed to agree with the predictions the theory survives, and our confidence in it is increased; but if ever a new observation is found to disagree, we have to abandon or modify the theory.

Stephen Hawking
It would be very difficult to explain why the universe should have begun in just this way, except as the act of a God who intended to create beings like us

Stephen Hawking
Someone told me that each equation I included in the book would halve the sales. I therefore resolved not to have any equations at all. In the end, however, I did put in one equation, Einstein's famous equation, E = mc squared. I hope that this will not scare off half of my potential readers.

Stephen Hawking
The universe would have expanded in a smooth way from a single point. As it expanded, it would have borrowed energy from the gravitational field, to create matter. As any economist could have predicted, the result of all that borrowing, was inflation. The universe expanded and borrowed at an ever-increasing rate. Fortunately, the debt of gravitational energy will not have to be repaid until the end of the universe.

Stephen Hawking
One might think this means that imaginary numbers are just a mathematical game having nothing to do with the real world. From the viewpoint of positivist philosophy, however, one cannot determine what is real. All one can do is find which mathematical models describe the universe we live in. It turns out that a mathematical model involving imaginary time predicts not only effects we have already observed but also effects we have not been able to measure yet nevertheless believe in for other reasons. So what is real and what is imaginary? Is the distinction just in our minds?

Stephen Hawking
Asked what he thinks about most during the day:
Women. They are a complete mystery.

Stephen Hawking
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.

Stephen Hawking
The rate of progress is so rapid that what one learns at school or university is always a bit out of date. Only a few people can keep up with the rapidly advancing frontier of knowledge, and they have to devote their whole time to it and specialize in a small area. The rest of the population has little idea of the advances that are being made or the excitement they are generating.

Stephen Hawking
Scientists have become the bearers of the torch of discovery in our quest for knowledge.

Stephen Hawking
On the possibility of contact with an alien civilization:
I think it would be a disaster. The extraterrestrials would probably be far in advance of us. The history of advanced races meeting more primitive people on this planet is not very happy, and they were the same species. I think we should keep our heads low.

Stephen Hawking
To show this diagram properly, I would really need a four dimensional screen. However, because of government cuts, we could manage to provide only a two dimensional screen.

Stephen Hawking