38. "Nature has created us solely to be happy." This is a statement of the doctrine, which La Mettrie develops in his principal ethical work "Discours sur le Bonheur." He teaches that happiness rests upon bodily pleasure and pain. In "L'histoire naturelle de l'âme," La Mettrie states that all the passions can be developed from two fundamental passions, of which they are but modifications, love and hatred, or desire and aversion. [100] Like La Mettrie, Helvetius makes corporeal pleasure and pain the ruling motives for man's conduct. Thus he writes: "Pleasure and pain are and always will be the only principles of action in man." [101]... "Remorse is nothing more than a foresight of bodily pain to which some crime has exposed us." [102] He definitely makes happiness the end of human action. "The end of man is self-preservation and the attainment of a happy existence.... Man, to find happiness, should save up his pleasures, and refuse all those which might change into pains.... The passions always have happiness as an object: they are legitimate and natural, and can not be called good or bad except on account of their influence on human beings. To lead men to virtue, we must show them the advantages of virtuous actions." [103] Holbach, finally, goes further than La Mettrie or Helvetius, and makes purely mechanical impulses the motives of man's action. "The passions are ways of being or modifications of the internal organs, attracted or repulsed by objects, and are consequently subject in their own way to the physical laws of attraction and repulsion." [104] 39. "Ixions of Christianity." Ixion, for his treachery, stricken with madness, was cast into Erebus, where he was continually scourged while bound to a fiery wheel, and forced to cry: "Benefactors should be honored." 40. "Who can be sure that the reason for man's existence is not simply the fact that he exists?" Luzac opposes this by saying: "If the reason of man's existence was in man himself, this existence would be a necessary consequence of his own nature; so that his own nature would contain the cause or reason of his existence. Now since his own nature would imply the cause of his existence, it would also imply his existence itself, so that man could no more be considered as non-existent than a circle can be considered without radii or a picture without features or proportions.... If the existence of man was in man himself, he would then be an invariable being." [105]