Hilary Putnam tell the story of his taking to his supervisor, Hans Reichenbach, a copy of Quine’s ‘Two Dogmas of Empiricism’. Putnam told Reichenbach: “it is an extraordinary paper; Quine argues that the difference between the analytic and the synthetic is not a difference of kind, but one of degree.” Reichenbach looked puzzled and then replied “Hilary, is the difference between a difference of kind and one of degree a difference of kind or one of degree?”.