[Tloewald]

It seems to me that concern over the dictatorship criterion is ill founded. Its failure merely implies that for any given set of alternatives there will always be one voter whose preferences, whatever they may be, determine the outcome. Now if everyone's preferences were known and constant then in theory you could find that person and they would be able to decide the outcome. In practice preferences don't stay constant and no-one knows them all, so as long as you have secret ballots the dictatorship criterion doesn't matter. So you can have the other two criteria which are far more important.