"If preachers have not yet overtly identified themselves with the view of the natural man, expressed by an eighteenth-century writer in the words, "trade is one thing and religion is another," they imply a not very different conclusion by their silence as to the possibility of collisions between them. The characteristic doctrine was one, in fact, which left little room for religious teaching as to economic morality, because it anticipated the theory, later epitomized by Adam Smith in his famous reference to the invisible hand, which saw in economic self-interest the operation of a providential plan. ..."