If in ten throws [of a die] I obtain “1” six times, then I will conjecture that something is wrong with the probability prediction [P(1) = 1/6]; if, say, in the very next five throws I get “1” two of three times again, I will be convinced that the prediction (for this case), and with its specific assumptions, are falsified: I will try to change the assumptions. Initially, I will not change the natural laws but assume that certain other assumptions were false. Above all, I will examine whether the die is not “loaded” (whether the centre of gravity of this die is at its geometric centre, etc.). (p. 152)
Popper, K. (2012). The two fundamental problems of the theory of knowledge. London: Routledge Classics. (Originally published 1978)