
Kurt Gödel (1958, CW II, p. 241) as cited in: Feferman, Solomon. " Lieber Herr Bernays!, Lieber Herr Gödel! Gödel on finitism, constructivity and Hilbert's program* http://math.stanford.edu/~feferman/papers/bernays.pdf." dialectica 62.2 (2008): 179-203.