- completeness: if A and B are any 2 situations, an individual can always specify exactly on of the following options: A ≽ B, B ≽ A, A ~ B (indifferent between A and B) - transitivity: if A is preferred to B, and B is preferred to C, then A is preferred to C, assuming that the individual's choices are internally consistent - continuity: if A is preferred to B, the situations suitably "close to" A must also be preferred to B; used to analyze individuals responses to relatively small changes in income and prices - strict monotonicity: more is better, so if A has more than B (A > B), then A ≽ B - strict convexity: averages are preferred to extremes, mixture is preferred