The acceptance of the doctrine of 'final causes' was the inevitable course for a philosopher who wishes to retain the old creeds and yet to appeal unequivocally to experience. It suits the amiable optimism for which Stewart is noticeable. To prove the existence of a perfect deity from the evidence afforded by the world, you must of course take a favourable view of the observable order. Stewart shows the same tendency in his Political Economy, where he is Adam Smith's disciple, and fully shares Smith's beliefs that the harmony between the interests of the individual and the interests of the society is an evidence of design in the Creator of mankind. In this respect Stewart differs notably from Butler, to whose reasonings he otherwise owed a good deal. With Butler the conscience implies a dread of divine wrath and justifies the conception of a world alienated from its maker. Stewart's 'moral faculty' simply recognises or reveals the moral law; but carries no suggestion of supernatural penalties. The doctrines by which Butler attracted some readers and revolted others throw no shadow over his writings. He is a placid enlightened professor, whose real good feeling and frequent shrewdness should not be overlooked in consequence of the rather desultory and often superficial mode of reasoning. This, however, suggests a final remark upon Stewart's position.
In the preface[199] to his _Active and Moral Powers_ (1828) Stewart apologises for the large space given to the treatment of Natural Religion. The lectures, he says, which form the substance of the book, were given at a time when 'enlightened zeal for liberty' was associated with the 'reckless boldness of the uncompromising freethinker.' He wished, therefore, to show that a man could be a liberal without being an atheist. This gives the position characteristic of Stewart and his friends. The group of eminent men who made Edinburgh a philosophical centre was thoroughly in sympathy with the rationalist movement of the eighteenth century. The old dogmatic system of belief could be held very lightly even by the more educated clergy. Hume's position is significant. He could lay down the most unqualified scepticism in his writings; but he always regarded his theories as intended for the enlightened; he had no wish to disturb popular beliefs in theology, and was a strong Tory in politics. His friends were quite ready to take him upon that footing. The politeness with which 'Mr. Hume's' speculations are noticed by men like Stewart and Reid is in characteristic contrast to the reception generally accorded to more popular sceptics. They were intellectual curiosities not meant for immediate application. The real opinion of such men as Adam Smith and Stewart was probably a rather vague and optimistic theism. In the professor's chair they could talk to lads intended for the ministry without insulting such old Scottish prejudice (there was a good deal of it) as survived: and could cover rationalising opinions under language which perhaps might have a different meaning for their hearers. The position was necessarily one of tacit compromise. Stewart considers himself to be an inductive philosopher appealing frankly to experience and reason; and was in practice a man of thoroughly liberal and generous feelings. He was heartily in favour of progress as he understood it. Only he will not sacrifice common sense; that is to say, the beliefs which are in fact prevalent and congenial to existing institutions. Common sense, of course, condemns extremes: and if logic seems to be pushing a man towards scepticism in philosophy or revolution in practice, he can always protest by the convenient device of intuitions.