Few proposed axioms of rational preference have won universal acceptance, but by far the most controversial are the transitivity of (strict) preference and that of indifference. Both have been attacked in various ways. It is a curious fact, however, that critics have generally been more willing to abandon the latter than the former. Thus, Schick, while arguing at length against the transitivity of indifference, finds the transitivity of preference 'uncontestable'. 1 And Fishburn, though taking for granted the transitivity of preference, characterizes as 'rather unrealistic' the supposition that indifference is transitive. 2 A. F. MacKay, in his book Arrow's Theorem: The Paradox of Social Choice, Yale University Press, New Haven, 1980, goes a step further and actually suggests an explanation for why one should expect the one kind of transitivity and not the other. This is why there are counterexamples to the transitivity of indifference but not to the transitivity of (strict) preference. Indifference nontransitivity is supervenient upon perceptual nontransitivity --namely, the nontransitivity of perceptual discrimination failures. But strict preference presupposes discrimination success, and there are no nontransitivities of discrimination success. Hence, there are no counterexamples to the transitivity of strict preference (p. 54).