Calculators can only calculate - they cannot do mathematics.

Quantum computation is a distinctively new way of harnessing nature. It will be the first technology that allows useful tasks to be performed in collaboration between parallel universes.

If we suppose that many natural phenomena are in effect computations, the study of computer science can tell us about the kinds of natural phenomena that can occur.

I have not proved that the universe is, in fact, a digital computer and that it's capable of performing universal computation, but it's plausible that it is.

All physical systems can be thought of as registering and processing information, and how one wishes to define computation will determine your view of what computation consists of.

A computation is a process that obeys finitely describable rules.

Lately I’ve been working to convince myself that everything is a computation.

There is something going on in time and space, and beyond time and space, which, whether we like it or not, spells duty.

The desire to economize time and mental effort in arithmetical computations, and to eliminate human liability to error is probably as old as the science of arithmetic itself.

Truth is ever to be found in the simplicity, and not in the multiplicity and confusion of things.

Computer science is no more about computers than astronomy is about telescopes.

Nature laughs at the difficulties of integration.

If you think of your life as a kind of computation, it's quite abundantly clear that there's not going to be a final answer and there won't be anything particularly wonderful about having the computation halt!

No sociologist should think himself too good, even in his old age, to make tens of thousands of quite trivial computations in his head and perhaps for months at a time.

One of the things that I've been doing recently in my scientific research is to ask this question: Is the universe actually capable of performing things like digital computations?

Computer scientists have so far worked on developing powerful programming languages that make it possible to solve the technical problems of computation. Little effort has gone toward devising the languages of interaction.

Computations are everywhere, once you begin to look at things in a certain way.

Mathematics is no more computation than typing is literature.

We are not very pleased when we are forced to accept a mathematical truth by virtue of a complicated chain of formal conclusions and computations, which we traverse blindly, link by link, feeling our way by touch. We want first an overview of the aim and of the road; we want to understand the idea of the proof, the deeper context.

To me quantum computation is a new and deeper and better way to understand the laws of physics, and hence understanding physical reality as a whole.

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