ABSTRACT
Even in its most simple praxiological meaning, the idea of rationality poses numerous problems of definition. Generally, if a specific collection of means exists to arrive at an end, if these means can be totally ordered in relation to one criterion (this criterion could be for example the cost, the difficulty, the accessibility of each means), rational action is that which utilizes the best means in relation to this criterion. But these conditions (overall order in relation to an unique criterion of a finished collection of means) may not all be united (and often are not). If they are objectively united, they may not be so in the consciousness of the actor, who may for example have no knowledge of such and such a means. The notion of rationality, in the praxiological sense of the term, is thus only unequivocally defined in limited situations.
