Scottish common sense philosophy a comprehensive philosophical position developed by Reid in the latter part of the eighteenth century. Reid’s views were propagated by a succession of Scottish popularizers, of whom the most successful was Dugald Stewart. Through them common sense doctrine became nearly a philosophical orthodoxy in Great Britain during the first half of the nineteenth century. Brought to the United States through the colleges in Princeton and Philadelphia, common sensism continued to be widely taught until the later nineteenth century. The early Reidians Beattie and Oswald were, like Reid himself, read in Germany by Kant and others; and Reid’s views were widely taught in post-Napoleonic France. The archenemy for the common sense theorists was Hume. Reid saw in his skepticism the inevitable outcome of Descartes’s thesis, accepted by Locke, that we do not perceive external objects directly, but that the immediate object of perception is something in the mind. Against this he argued that perception involves both sensation and certain intuitively known general truths or principles that together yield knowledge of external objects. He also argued that there are many other intuitively known general principles, including moral principles, available to all normal humans. As a result he thought that whenever philosophical argument results in conclusions that run counter to common sense, the philosophy must be wrong.
Stewart made some changes in Reid’s acute and original theory, but his main achievement was to propagate it through eloquent classes and widely used textbooks. Common sensism, defending the considered views of the ordinary man, was taken by many to provide a defense of the Christian religious and moral status quo. Reid had argued for free will, and presented a long list of self-evident moral axioms. If this might be plausibly presented as part of the common sense of his time, the same could not be said for some of the religious doctrines that Oswald thought equally self-evident. Reid had not given any rigorous tests for what might count as selfevident. The easy intuitionism of later common sensists was a natural target for those who, like J. S. Mill, thought that any appeal to self-evidence was simply a way of justifying vested interest. Whewell, in both his philosophy of science and his ethics, and Sidgwick, in his moral theory, acknowledged debts to Reid and tried to eliminate the abuses to which his method was open. But in doing so they transformed common sensism beyond the limits within which Reid and those shaped by him operated.
See also HUME, MOORE, REID, SIDGWIC. J.B.S.