Karl Raimund Popper

Sir Karl Raimund Popper (1902 - 1994) was an Austrian-born British philosopher of science, known for his theory of scientific method and for his criticism of historical determinism.

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 Raimund Popper

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

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

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

We must plan for freedom, and not only for security, if for no other reason than that only freedom can make security secure.
Karl Raimund Popper

Science may be described as the art of systematic over-simplification.
Karl Raimund Popper

Our civilization has not yet fully recovered from the shock of its birth: the transition from the tribal or 'closed society', with its submission to magical forces, to the 'open society' which sets free the critical powers of man.
Karl Raimund Popper

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