227 Quotes by Karl Popper

Science is most significant as one of the greatest spiritual adventures that man has yet known.

Those who promise us paradise on earth never produced anything but a hell.

We should therefore claim, in the name of tolerance, the right not to tolerate the intolerant.

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

All we can do is search for the falsity content in our best theory.

In so far as a scientific statement speaks about reality, it must be falsifiable; and in so far as it is not falsifiable, it does not speak about reality.

We never know what we are talking about.

The true Enlightenment thinker, the true rationalist, never wants to talk anyone into anything. No, he does not even want to convince; all the time he is aware that he may be wrong. Above all, he values the intellectual independence of others too highly to want to convince them in important matters. He would much rather invite contradiction, preferably in the form of rational and disciplined criticism. He seeks not to convince but to arouse - to challenge others to form free opinions.

Our knowledge can only be finite, while our ignorance must necessarily be infinite.