heart and conscience in their interpretation of the world and of human life. It was in 1774 that Reid’s appeal in 1764 to the common reason of human nature aroused hostile criticism. He had been seconded by others in his response to the sceptics. The resort to a ‘sense’ of self-evident truth, in his _Inquiry_ in 1764, which itself looked like a reply to argument by feeling, was followed in 1766 by _An Appeal to Common Sense on behalf of Religion_, by Dr. James Oswald, minister of Methven in Perthshire. In 1770 Beattie’s _Essay on the Nature and Immutability of Truth, in opposition to Sophistry and Scepticism_, followed. Oswald and Beattie were not deep and patient thinkers like Reid;[19] but the rising literary and social reputation of Beattie, secured for the _Essay on Truth_ more rapid and widespread admiration than was given to the _Inquiry_. Beattie often visited London, was there one of the lions of the day, was made a D.C.L. of Oxford, and had interviews with George the Third, who admired his book, conferred a pension on Beattie, and rallied Mr. Dundas about ‘Scotch Philosophy.’ Reid, Beattie, and Oswald thus became known as a triumvirate of ‘Scottish Philosophers’; and the appeal to common sense, in which they were at least verbally agreed, began to be spoken about as ‘the Scottish Philosophy,’ a term which has since been adopted in this country and abroad. This Scottish triumvirate, helped into vogue by Beattie, roused Joseph Priestley, an English dissenter. Priestley had abandoned the Calvinism of his early creed for materialism, philosophical necessity, and free thought, and, after serving for some years as pastor of a nonconformist chapel in Cheshire, and next as a schoolmaster much devoted to experiments in the natural sciences, was already known as an author in natural science. In 1774, when he was living with Lord Shelburne, as librarian and literary companion, he appeared for the first time as a metaphysical critic, in _An Examination of Reid’s Inquiry, Beattie’s Essay, and Oswald’s Appeal to Common Sense_. He played upon the term ‘common sense,’ and took for granted that the aim of the triumvirate was to substitute mere feeling and authority for reason,—the authority of the multitude for that of the philosophical elect,—alleging blind instinct when unable to produce argument, and multiplying instincts to suit each controversial emergency. ‘As men have imagined innate ideas, because they had forgot how they came by their ideas, the Scottish philosophers set up almost as many distinct instincts as there are acquired principles of acting.’ He ridiculed Reid for his supposed discovery of the root of scepticism in the ideal hypothesis; charging him with innocently mistaking a metaphor for a scientific theory, and for overlooking the leading part which mental association plays, as the cause of those convictions which Reid mistook for infallible constituents of common sense. ‘If we consider the general tenor of the writings of