I have insisted that we must be tolerant. But I also believe that this tolerance has its limits. We must not trust… — Karl Popper Copy Share Image
The Conspiracy Theory of Society... [is] a typical result of the secularization of a religious superstition. The belief in the Homeric gods… — Karl Popper Copy Share Image
Optimism is a duty. The future is open. It is not predetermined. No one can predict it, except by chance. We all… — Karl Popper Copy Share Image
We do not choose political freedom because it promises us this or that. We choose it because it makes possible the only… — Karl Popper Copy Share Image
Science is not a system of certain, or -established, statements; nor is it a system which steadily advances towards a state of finality... And… — Karl Popper Copy Share Image
“As indicated by our example, methodological nominalism is nowadays fairly generally accepted in the natural sciences. The problems of the social sciences, on the… — Karl Popper Copy Share Image
Science is perhaps the only human activity in which errors are systematically criticized and, in time, corrected. — Karl Popper Copy Share Image
A system is empirical or scientific only if it is capable of being tested by experience. These considerations suggest that not the verifiability but… — Karl Popper Copy Share Image
Bold ideas, unjustified anticipations, and speculative thought, are our only means for interpreting nature: our only organon, our only instrument, for grasping her. And… — Karl Popper Copy Share Image
[The aim of science is] to explain what so far has taken to be an explicans, such as a law of nature. The task… — Karl Popper Copy Share Image
There can be no ultimate statements science: there can be no statements in science which can not be tested, and therefore none which cannot… — Karl Popper Copy Share Image
Evolution is not a fact. Evolution doesn't even qualify as a theory or as a hypothesis. It is a metaphysical research program, and it… — Karl Popper Copy Share Image
I am opposed to looking upon logic as a kind of game. ... One might think that it is a matter of choice or… — Karl Popper Copy Share Image
The history of science, like the history of all human ideas, is a history of irresponsible dreams, of obstinacy, and of error. — Karl Popper Copy Share Image