Karl Popper's paradox of tolerance is a concept that addresses a seeming contradiction within the idea of tolerance, the acceptance of different views and practices. Popper, who was our patron, discussed this paradox in his 1945 book, 'The Open Society and Its Enemies.' The paradox is based on the observation that if a society is tolerantly indiscriminate and extends tolerance to those who are intolerant, the ability of the society to be tolerant will eventually be undermined and destroyed by the intolerant. Popper argues that in order to maintain a tolerant society, it must be intolerant of intolerance. This doesn't mean that we should always suppress the expression of intolerant beliefs. However, Popper suggests that society must reserve the right to prevent intolerant groups or individuals from destroying the tolerance of society as a whole. He essentially proposes a rational limit to tolerance, suggesting that we shouldn't tolerate intolerance to the extent that it leads to the destruction of tolerance itself. The paradox lies in the counterintuitive idea that in order to maintain a tolerant society, there must be some form of intolerance (namely, against intolerance). It raises important ethical and practical questions about how societies can and should balance the values of freedom of expression and tolerance with the need to protect themselves against forces that would undermine those very values. Graphic by @pictoline.