 In the Twentieth Century, economists stripped this theory of its hedonistic clothing (Pareto 1909, Hicks and Allen 1934). Rather than supposing that all consumption choices can be ranked by how much they promote an agent’s happiness, economists focused on the ranking itself. All that they suppose concerning evaluations is that agents are able consistently to rank the alternatives they face. This is equivalent to supposing first that rankings are complete — that is, for any two alternatives x and y that the agent considers, either the agent ranks x above y (prefers x to y), or the agent prefers y to x, or the agent is indifferent. Second, economists suppose that agent’s rankings of alternatives (preferences) are transitive. To say that an agent’s preferences are transitive is to claim that if the agent prefers x to y and y to z, then the agent prefers x to z, with similar claims concerning indifference and combinations of indifference and preference. Though there are further technical conditions to extend the theory to infinite sets of alternatives and to capture further plausible rationality conditions concerning gambles, economists generally subscribe to a view of rational agents as at least possessing complete and transitive preferences and as choosing among the feasible alternatives whichever they most prefer. In the theory of revealed preference, economists have attempted unsuccessfully to eliminate all reference to subjective preference or to define preference in terms of choices (Samuelson 1947, Houtthaker 1950, Little 1957, Sen 1971, 1973, Hausman 2012, chapter 3).