Quotes from Karl Popper

I, however, believe that there is at least one philosophical problem, It is the problem of cosmology

while I felt that the Marxist attitude towards their theory was not at all admirable but was typically dogmatic and had all these properties which the Marxists usually said were characteristic of the churches. So I realized fairly early that Marxism was more of a church than of a science.

Indeed, he said as late as 1976 that he would have remained a socialist all his life if he had thought that it was possible to reconcile socialist egalitarianism with freedom.

Popper was already working towards his 'fallibilist' view that theories can never be proved, although they can be decisively disproved—but it had survived a severe test, and had emerged as a theory worth embracing.

At least some of them, I suspect, have turned to probability theory in the hope that it would give them what they had originally expected from a subjectivist or epistemological theory of the attainment of truth through verification; that is, a theory of rational and justifiable belief, based upon observed instances.

Science is a 'trial and error' learning process, and one of the virtues of an open society is its ability to learn from experience. Closed societies resist novelty and therefore pass up the chance to learn from experience.

Popper espoused what became known as 'falsificationism', the doctrine that what we are interested in the sciences is the conditions under which we should reject a proposed law or theory; the proposition that 'all swans are white' is decisively refuted by one black swan, no matter how often it has been 'verified' by sightings of white swans.

Like many others of his generation, he came to suspect that sustaining a lively and innovative economic system might place more constraints on the pursuit of equality than he had once thought.

what characterizes the empirical method is its manner of exposing to falsification, in every conceivable way, the system to be tested. Its aim is not to save the lives of untenable systems but, on the contrary, to select the one which is by comparison the fittest, by exposing them all to the fiercest struggle for survival.

By criticizing our theories we can let our theories die in our stead.

In the empirical sciences, which alone can furnish us with information about the world we live in, proofs do not occur, if we mean by 'proof' an argument which establishes once and for ever the truth of a theory.

But we must realize that even this tendency to restrict the exploitation of class privileges is a fairly common ingredient of totalitarianism. Totalitarianism is not simply amoral. It is the morality of the closed society—of the group, or of the tribe; it is not individual selfishness, but it is collective selfishness.

It is not difficult to show that a theory of democratic control can be developed which is free of the paradox of sovereignty. The theory I have in mind is one which does not proceed, as it were, from a doctrine of the intrinsic goodness or righteousness of a majority rule, but rather from the baseness of tyranny; or more precisely, it rests upon the decision, or upon the adoption of the proposal, to avoid and to resist tyranny." Karl Popper, 'The Open Society and Its Enemies', Chapter 7.

It will for ever remain one of the greatest triumphs of Athenian democracy that it treated slaves humanely, and that in spite of the inhuman propaganda of philosophers like Plato himself and Aristotle it came, as he witnesses, very close to abolishing slavery.

Instead of posing as prophets, we must become the makers of our fate. We must learn to do things as well as we can, and to look out for our mistakes. And when we have dropped the idea that the history of power will be our judge, when we have given up worrying whether or not history will justify us, then one day perhaps we may succeed in getting our power under control. In this way we may even justify history, in our turn. It badly needs a justification.

We must not act like children reared with the narrow outlook "As it has been handed down to us".

While an uncritical animal may be eliminated altogether with its dogmatically held hypotheses, we may formulate our hypotheses, and criticize them. Let our conjectures, our theories die in our stead!

Never can an authority admit that the intellectually courageous - those who dare to defy his authority - may be the most valuable type.

All nationalism or racialism is evil, and Jewish nationalism is no exception.

Recuerda que es imposible hablar de manera que no se te malinterprete. Siempre habrá alguien que lo haga.

Some philosophers have made a virtue of talking to themselves; perhaps because they felt that there was nobody else worth talking to. I fear that the practice of philosophizing on this somewhat exalted plane may be a symptom of the decline of rational discussion. No doubt God talks mainly to Himself because He has no one worth talking to. But a philosopher should know that he is no more godlike that any other man. (pp xx)

But the approach to truth is not easy. There is only one way towards it, the way through error. Only through our errors can we learn; and only he will learn who is ready to appreciate and even to cherish the errors of others as stepping stones towards truth, and who searches for his own errors: who tries to find them, since only when he has become aware of them can he free himself from them.

We may become the makers of our fate when we have ceased to pose as its prophets.

Heraclitean philosophy one of the less commendable characteristics of historicism manifests itself, namely, an over-emphasis upon change, combined with the complementary belief in an inexorable and immutable law of destiny.