The old scientific ideal of episteme – of absolutely certain, demonstrable knowledge – has proved to be an idol. The demand for scientific objectivity makes it inevitable that every scientific statement must remain tentative for ever.
A theory is just a mathematical model to describe the observations.
Man, some modern philosophers tell us, is alienated from his world: he is a stranger and afraid in a world he never made. Perhaps he is; yet so are animals, and even plants. They too were born, long ago, into a physico-chemical world, a world they never made.
Our belief in any particular natural law cannot have a safer basis than our unsuccessful critical attempts to refute it.
Good tests kill flawed theories; we remain alive to guess again.
The future is always present, as a promise, a lure and a temptation.
The scientific tradition is distinguished from the pre-scientific tradition by having two layers. Like the latter, it passes on its theories; but it also passes on a critical attitude towards them.
It is part of my thesis that all our knowledge grows only through the correcting of our mistakes.
Optimism is a duty. The future is open. It is not predetermined. No one can predict it, except by chance. We all contribute to determining it by what we do. We are all equally responsible for its success.
Plato felt that a complete reconstruction of society’s political program was needed.
Our knowledge can only be finite, while our ignorance must necessarily be infinite.
You cannot have a rational discussion with a man who prefers shooting you to being convinced by you.
Contrary to the outstanding work of art, outstanding theory is susceptible to improvements.
The fundamental thing about human languages is that they can and should be used to describe something; and this something is, somehow, the world. To be constantly and almost exclusively interested in the medium – in spectacle-cleaning – is a result of a philosophical mistake.
The defence of democracy must consist in making anti-democratic experiences too costly for those who try them; much more costly than a democratic compromise.
We do not know anything – this is the first. Therefore, we should be very modest – this is the second. Not to claim that we do know when we do not – this is the third. That’s the kind of attitude I’d like to popularize. There is little hope for success.
Piecemeal social engineering resembles physical engineering in regarding the ends as beyond the province of technology.
If we are not prepared to defend a tolerant society against the onslaught of the intolerant, then the tolerant will be destroyed, and tolerance with them.
I have insisted that we must be tolerant. But I also believe that this tolerance has its limits. We must not trust those anti-humanitarian religions which not only preach destruction but act accordingly. For if we tolerate them, then we become ourselves responsible for for their deeds.
Every discovery contains an irrational element or a creative intuition.