Downloadable PDF (IN CASE THE TEXT BELOW IS UNREADABLE) Preprint 6/20/2019 Copyright Not So Fast Qbists - - The Frequency Operator Derivation Of Born’s Rule Is OK! David Carlyle Anacker, PhD Physics The business of this essay is to refute the main objection 1,2,3 , commonly proffered by Qbists, to the frequency operator derivation of Born’s rule in quantum mechanics. Qbism, short for quantum Bayesianism, is an interpretation of quantum mechanics in terms of subjective Bayesian probability. A more general critique of Qbism and associated bibliography may be found by Googling Marian Kupczynski’s Correspondnce to: marian.kupczynski@uqo.ca entitled “Greeks were right: critical comments on Qbism”. Let us assume ïY ñ = c ï 0ñ + s ï 1ñ is unity normalized and for convenience c , s both real. (The same conclusions can be reached for complex c, s.) Also let êY N ñ = çYñçYñ ...N factors... çYñ, with due apologies for omitting Ä here and throughout