The Bactra Review Why So
Slow?
See Popper's The Open Society and Its Enemies (London: Routledge,
1945, and numerous subsequent editions), esp. vol. I. Arguments very similar
to Popper's were advanced some years earlier by L. Susan Stebbing in her
Ideals and Illusions (London: Watts and Co., 1941), and since
Stebbing knew Popper, and even helped him get a job, it's possible he was
influenced by her on this point.