The social aim is to produce things useful to life; the final end of social activity is ‘the exploitation of the globe by association.’ The contrast between labour and capital, so much emphasised by later socialism, is not present to Saint-Simon, but it is assumed that the industrial chiefs, to whom the control of production is to be committed, shall rule in the interest of society. Later on, the cause of the poor receives greater attention, till in his greatest work, _The New Christianity_, it becomes the central point of his teaching, and takes the form of a religion. It was this religious development of his teaching that occasioned his final quarrel with Comte. Previous to the publication of the _Nouveau Christianisme_ Saint-Simon had not concerned himself with theology. Here he starts from a belief in God, and his object in the treatise is to reduce Christianity to its simple and essential elements. He does this by clearing it of the dogmas and other excrescences and defects that have gathered round both the Catholic and Protestant forms of it, which he subjects to a searching and ingenious criticism. The moral doctrine will by the new faith be considered the most important; the divine element in Christianity is contained in the precept that men should act towards one another as brethren. ‘The new Christian organisation will deduce the temporal institutions as well as the spiritual from the principle that all men should act towards one another as brethren.’ Expressing the same idea in modern language, Saint-Simon propounds as the comprehensive formula of the new Christianity this precept: ‘The whole of society ought to strive towards the amelioration of the moral and physical existence of the poorest class; society ought to organise itself in the way best adapted for attaining this end.’ This principle became the watchword of the entire school of Saint-Simon; for them it was alike the essence of religion and the programme of social reform.