Karl Popper Quotes

Of course I shall go astray often...for who does not make mistakes? But I cannot go far wrong for I have seen the truth.

Science never gives up searching for truth, since it never claims to have achieved it.

We never are definitely right, we can only be sure we are wrong.

No doubt about it: error is the rule, truth is the accident of error.

Knowledge being to be had only of visible and certain truth, error is not a fault of our knowledge, but a mistake of our judgment, giving assent to that which is not true.

Error is certainty's constant companion. Error is the corollary of evidence. And anything said about truth may equally well be said about error: the delusion will be no greater.

My passion is for scientific truth. I don't much care about good and evil. ... I care about what's true.

Scientists do not believe in fundamental and absolute certainties. For the scientist, certainty is never an end, but a search; not the ordering of certainty, but its exploration. For the scientist, certainty represents the highest degree of probability.

Science is a tribute to what we can know, although we are fallible.

There is not a single truth of science upon which we ought to bet more than about a million of millions to one.

Medicine being a compendium of the successive and contradictory mistakes of medical practitioners, when we summon the wisest of them to our aid, the chances are that we may be relying on a scientific truth the error of which will be recognized in a few years time.

When a man tells you that he knows the exact truth about anything you are safe in inferring that he is an inexact man.

Vast ills have followed a belief in certainty.

All knowledge degenerates into probability.

The bad news is we don't have any control. The good news is we can't make any mistakes.

I know I got to be right now Cause I can't get much wronger

When a scientist doesn't know the answer to a problem, he is ignorant. When he has a hunch as to what the result is, he is uncertain. And when he is pretty darn sure of what the result is going to be, he is in some doubt.

Grown people know that they do not always know the way of things, and even if they think they know, they do not know where and how they got the proof.

You will get something wrong today, and tomorrow, and every day of your life. So will I, and everybody you know. You don’t have a choice about being wrong sometimes: mistakes will be your life-long companion. But you do have a choice about whether to approach your error in terror so you suppress, ignore and repeat it — or to make it your honest, open ally in trying to get to the truth.

It is not that there are no certainties, it is that it is an absolute certainty that there are no certainties.

... no bell in us tolls to let us know for certain when truth is in our grasp.

Remember that [scientific thought] is the guide of action; that the truth which it arrives at is not that which we can ideally contemplate without error, but that which we may act upon without fear; and you cannot fail to see that scientific thought is not an accompaniment or condition of human progress, but human progress itself.

You correct an error by bringing truth to it.

I make a hundred mistakes a day. I am, and have been, and will continue to be, wrong about almost everything.

True' and 'false' are the evasions of people who never want to arrive at a decision. Truth is something without end.