The paradox of tolerance is a paradox that states that if a society is tolerant without limit, its ability to be tolerant is eventually seized or destroyed by the intolerant.

Karl Popper first described it in 1945—expressing the seemingly paradoxical idea that, "In order to maintain a tolerant society, the society must be intolerant of intolerance."

Restricting access to knowledge and science is not beneficial for society. So why are scientific results still locked up behind paywalls? Even though the answer to this question is enlightening, the story is quickly told. Much more important is the knowledge on how to change this.