Karl Popper, the Philosophy of Science, and the Paradox of Tolerance

Karl Popper (pictured here) was a 20th Century philosopher of science, perhaps best known for his belief that if we are to call any idea a “scientific theory,” it needs to be falsifiable, i.e., that there needs to be a way of subjecting it to an experiment in which we are capable of proving it false.

Popper died long before string theory came along in physics, but it’s clear that he would have called this “theory” a religion rather than a part of science, since, even today, there is no conceivable experiment that would disprove it.

Popper is also well known for his “paradox of tolerance,” i.e., his reasoning that leads to the conclusion: The only thing we must not tolerate is intolerance, as explained in the graphic below.  How important this notion is in today’s world.