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

True ignorance is not the absence of knowledge, but the refusal to acquire it. — Karl Popper

The growth of knowledge depends entirely upon disagreement. — Karl Popper

Ignorance is not a simple lack of knowledge but an active aversion to knowledge, the refusal to know, issuing from cowardice, pride, or laziness of mind. — Karl Popper

It is part of my thesis that all our knowledge grows only through the correcting of our mistakes. — Karl Popper

Science may be described as the art of systematic oversimplification. — Karl Popper

Science must begin with myths, and with the criticism of myths. — Karl Popper

The history of science, like the history of all human ideas, is a history of irresponsible dreams, of obstinacy, and of error. — Karl Popper

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 is not really testable science. — Karl Popper

It is the rule which says that the other rules of scientific procedure must be designed in such a way that they do not protect any statement in science against falsification. — Karl Popper

What really makes science grow is new ideas, including false ideas. — Karl Popper

It is not his possession of knowledge, of irrefutable truth, that makes the man of science, but his persistent and recklessly critical quest for truth. — Karl Popper

Reason like science, grows by way of mutual criticism; the only possible way of planning its growth is to develop those institutions that safeguard. the freedom of thought — Karl Popper

It is a myth that the success of science in our time is mainly due to the huge amounts of money that have been spent on big machines. What really makes science grow is new ideas, including false ideas. — Karl Popper

The game of science is, in principle, without end. He who decides one day that scientific statements do not call for any further test, and that they can be regarded as finally verified, retires from the game. — Karl Popper

You cannot have a rational discussion with a man who prefers shooting you to being convinced by you. — Karl Popper

A rational analysis of the consequences of a decision does not make the decision rational; the consequences do not determine our decision; it is always we who decide. — Karl Popper

No rational argument will have a rational effect on a man who does not want to adopt a rational attitude. — Karl Popper

Serious rational criticism is so rare that it should be encouraged. Being too ready to defend oneself is more dangerous than being too ready to admit a mistake. — Karl Popper

The best thing that can happen to a human being us to find a problem, to fall in love with that problem, and to live trying to solve that problem, unless another problem even more lovable appears. — Karl Popper

There is no history of mankind, there are only many histories of all kinds of aspects of human life. And one of these is the history of political power. This is elevated into the history of the world. — Karl Popper

The history of science is everywhere speculative. It is a marvelous hiatory. It makes you proud to be a human being. — Karl Popper

Science is perhaps the only human activity in which errors are systematically criticized and, in time, corrected. — Karl Popper

Better our hypotheses die for our errors than ourselves. — Karl Popper

I have spoken to Einstein and he admitted to me that his theory was in fact no different from the one of Parmenides. — Karl Popper

It is impossible to speak in such a way that you cannot be misunderstood. — Karl Popper

The initial stage, the act of conceiving or inventing a theory, seems to me neither to call for logical analysis nor to be susceptible of it. — Karl Popper

Always remember that it is impossible to speak in such a way that you cannot be misunderstood: there will always be some who misunderstand you. — Karl Popper

Contrary to the outstanding work of art, outstanding theory is susceptible to improvements. — Karl Popper

Historically speaking all–or very nearly all–scientific theories originate from myths. — Karl Popper

The only way to test a hypothesis is to look for all the information that disagrees with it. — Karl Popper

We do not know. We can only guess. — Karl Popper

Definitions…. are never really needed, and rarely of any use — Karl Popper

Every genuine test of a theory is an attempt to falsify it, or to refute it. — Karl Popper

A theory is just a mathematical model to describe the observations. — Karl Popper

No number of sightings of white swans can prove the theory that all swans are white. The sighting of just one black one may disprove it. — Karl Popper

To] interpret Parmenides as a Kant before Kant … this is exactly what we must do. — Karl Popper

The conspiracy theory of society… comes from abandoning god and then asking: ‘Who is in his place — Karl Popper

I have come to the conclusion that Darwinism is not a testable scientific theory, but a metaphysical research programme. — Karl Popper

There is no pure, disinterested, theory–free observation. — Karl Popper

Whenever a theory appears to you as the only possible one, take this as a sign that you have neither understood the theory nor the problem which it was intended to solve. — Karl Popper

There will be well–testable theories, hardly testable theories, and non–testable theories. Those which are non–testable are of no interest to empirical scientists. They may be described as metaphysical. — Karl Popper

No particular theory may ever be regarded as absolutely certain…. No scientific theory is sacrosanct. — Karl Popper

We hate the very idea that our own ideas may be mistaken, so We cling dogmatically to our conjectures. — Karl Popper

Our belief in any particular natural law cannot have a safer basis than our unsuccessful critical attempts to refute it. — Karl Popper

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

No matter how many instances of white swans we may have observed, this does Not justify the conclusion that all swans are white. — Karl Popper

A theory which is not refutable by any conceivable event is nonscientific. Irrefutability is not a virtue of a theory (as people often think) but a vice. — Karl Popper

Good tests kill flawed theories; we remain alive to guess again. — Karl Popper