Philosopher Karl Popper defined the paradox in 1945 in The Open Society and Its Enemies Vol. 1.

https://infogalactic.com/info/Karl_Popper

arl Popper was born in Vienna (then in Austria-Hungary) in 1902, to upper middle-class parents. All of Karl Popper's grandparents were Jewish but were not devout, and as part of the cultural assimilation process, the Popper family converted to Lutheranism before Karl was born,[16][17] and so he received Lutheran baptism.