Karl Popper

Knowledge advances by the follies of mankind.

It is the job of science to question every assumption.

History is not a simple linear development; it is a process of trial and error.

All human knowledge is based on the ideas of conjecture and refutation.

In an open society, it is not the majority that is always right.

A society that is open to change is a society that can progress.

Our ideas must be tested and challenged continually.

A rational society should be open to all ideas, even those we disagree with.

The growth of scientific knowledge is based on the critical discussion of existing theories.

The open society is a society in which individuals are free to express themselves.