David Deutsch Quotes

Perhaps a more practical way of stressing the same truth would be to frame the growth of knowledge (all knowledge, not only scientific) as a continual transition from problems to better problems, rather than from problems to solutions or from theories to better theories. This

If you reject the infinite, you are stuck with the finite, and the finite is parochial ... the best explanation of anything eventually involves universality, and therefore infinity. The reach of explanations cannot be limited by fiat.

The most important application of quantum computing in the future is likely to be a computer simulation of quantum systems, because that's an application where we know for sure that quantum systems in general cannot be efficiently simulated on a classical computer.

I myself believe that there will one day be time travel because when we find that something isn't forbidden by the over-arching laws of physics we usually eventually find a technological way of doing it.

The most general way of stating the central assertion of the neo-Darwinian theory of evolution is that a population of replicators subject to variation (for instance by imperfect copying) will be taken over by those variants that are better than their rivals at causing themselves to be replicated. This

Is the human race a universal constructor?

The most important of all limitations on knowledge – creation is that we cannot prophecy: we cannot predict the content of ideas yet to be created, or their effects. This limitation is not only consistent with the unlimited growth of knowledge, it is entailed by it.

From the least parochial perspectives available to us, people are the most significant entities in the cosmic scheme of things. They are not 'supported' by their environments, but support themselves by creating knowledge. Once they have suitable knowledge (essentially, the knowledge of the Enlightenment), they are capable of sparking unlimited further progress.

The theory that the biosphere was created without evolution, a few thousand years ago, is ruled out by overwhelming scientific evidence. To claim that there are 'alternative (always better) Biblical explanations of the same data', which make creationism a reasonable alternative to our best theories of biology and physics, is appalling intellectual dishonesty.

I chop and change between what is called 'work' and what is called 'recreation.' There are no discontinuities in my day. I only play tennis with people I find interesting.

The Enlightenment (The beginning of) a way of pursuing knowledge with a tradition of criticism and seeking good explanations instead of reliance on authority.

mechanical reinterpretations of human affairs not only lack explanatory power, they are morally wrong as well, for in effect they deny the humanity of the participants, casting them and their ideas merely as side effects of the landscape. Diamond

If we can't program it, we can't understand it.

The scientific revolution was part of a wider intellectual revolution, the Enlightenment, which also brought progress in other fields, especially moral and political philosophy, and in the institutions of society. Unfortunately, the term 'the Enlightenment' is used by historians and philosophers to denote a variety of different trends, some of them violently opposed to each other. What I mean by it will emerge here as we go along. It is one of several aspects of 'the beginning of infinity', and is a theme of this book. But one thing that all conceptions of the Enlightenment agree on is that it was a rebellion, and specifically a rebellion against authority in regard to knowledge.

No precautions, and no precautionary principle, can avoid problems that we do not yet foresee. We need a stance of problem-fixing, not just problem-avoidance.

The truly privileged theories are not the ones referring to any particular scale of size or complexity, nor the ones situated at any particular level of the predictive hierarchy, but the ones that contain the deepest explanations.

Bad philosophy before the Enlightenment was typically of the because-I-say-so variety. When the Enlightenment liberated philosophy and science, they both began to make progress, and increasingly there was good philosophy. But, paradoxically, bad philosophy became worse.

Base metals can be transmuted into gold by stars, and by intelligent beings who understand the processes that power stars, but by nothing else in the universe.

It is a mistake to conceive of choice and decision-making as a process of selecting from existing options according to a fixed formula. That omits the most important element of decision-making, namely the creation of new options. Good

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.

Sparta has no philosophers. That's because the job of a philosopher is to understand things better, which is a form of change, so they don't want it. Another difference: they don't honour living poets, only dead ones. Why? Because dead poets don't write anything new, but live ones do. A third difference: their education system is insanely harsh; ours is famously lax. Why? Because they don't want their kids to dare to question anything, so that they won't ever think of changing anything. How

Humans may or may not have cosmic significance, and if they do, it will be by hitching a ride on the objective centrality of knowledge in the cosmic scheme of things.

Where we have good, testable explanations, they then have to be tested, and we drop the ones that fail the tests.

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.

The whole [scientific] process resembles biological evolution. A problem is like an ecological niche, and a theory is like a gene or a species which is being tested for viability in that niche.

Trying to rely on the sheer good luck of avoiding bad outcomes indefinitely would simply guarantee that we would eventually fail without the means of recovering.

If it turns out that all this time we have merely been studying the programming of a cosmic planetarium, then that would merely mean that we have been studying a smaller portion of reality than we thought. So what? Such things have happened many times in the history of science, as our horizons have expanded beyond the Earth to include the solar system, our Galaxy, other galaxies, clusters of galaxies and so on, and, of course, parallel universes.

The brain is the only kind of object capable of understanding that the cosmos is even there, or why there are infinitely many prime numbers, or that apples fall because of the curvature of space-time, or that obeying its own inborn instincts can be morally wrong, or that it itself exists.

Because we are universal explainers, we are not simply obeying our genes. For

Copenhagen interpretation Niels Bohr's combination of instrumentalism, anthropocentrism and studied ambiguity, used to avoid understanding quantum theory as being about reality.

Like every other destruction of optimism, whether in a whole civilisation or in a single individual, these must have been unspeakable catastrophes for those who had dared to expect progress. But we should feel more than sympathy for those people. We should take it personally. For if any of those earlier experiments in optimism had succeeded, our species would be exploring the stars by now, and you and I would be immortal.

Every problem that is interesting is also soluble.

It is possible to build a virtual-reality generator whose repertoire includes every possible environment.

The overwhelming majority of theories are rejected because they contain bad explanations, not because they fail experimental tests.