Hamilton, SIR WILLIAM, of Preston, the most learned and scientific philosopher of the Scottish school, was born March 8, 1788, at Glasgow, where his father, Dr William Hamilton, and his grandfather, Dr Thomas Hamilton, held the chairs of Anatomy and Botany. Though the Hamiltons of Preston, in Haddingtonshire, who were raised to a baronetcy in 1673, had not assumed their title since the death of Sir William Hamilton in November 1688, when his brother and heir, Sir
Robert, the Covenanter, refused to take the oath of allegiance, the philosopher made good his claim to represent them, and therefore to be descended from the leader of the Covenanters at Bothwell Bridge. After gaining high distinction, especially in the philosophical classes, at Glasgow, he went in 1809 to Balliol College, Oxford, as a Snell exhibitor. He graduated with first-class honours in 1810; and it was here that he laid the basis of his vast erudition in medieval and modern, as well as in ancient literature. He left Oxford in 1813, and was called to the Scottish bar in 1813; but he seems never to have had any practice in his profession except what became incumbent on him on being appointed crown-solicitor of the Court of Teinds. In 1820, on the death of Dr Brown, he was an unsuccessful competitor for the chair of Moral Philosophy in Edinburgh; in 1821 he was appointed to the professorship of History.
Hamilton had now reached his thirtieth year without giving to the world any indication of those speculations which he had been silently and slowly maturing. But in 1829 there appeared in the Edinburgh Review a critique of Cousin's Cours de Philosophie of the previous year, in which was developed that philosopher's doctrine of the Infinite. The critique immediately excited admiration both at home and abroad, and for some years after this Hamilton was a regular contributor to the Edinburgh Review. Besides other philosophical articles, two of which, on the Philosophy of Perception and on Recent Publications in Logical Science, are especially celebrated, he contributed several papers on education and university reform. Many of these contributions were translated into German, French, and Italian; and in 1852 they were all edited by Hamilton himself, with notes and appendices, under the title of Discussions in Philosophy and Literature, Education, and University Reform. In 1836 Hamilton was elected to the chair of Logic and Metaphysics in Edinburgh. During his first session he delivered a course of lectures on metaphysics, which was followed in the succeeding session by a course on logic; and these two courses he continued to read each alternate year till the close of his life. His influence soon began to show itself in the university among the young men who were attracted thither from different parts of Scotland, and other countries, in many cases chiefly for the sake of hearing Hamilton. Extensive notes of his lectures were taken by his students, and numerous copies of them, transcribed from shorthand reports, were in circulation during the later years of his life. After his death these were published under the editorship of Professors Mansel and Veitch (Sir William Hamilton's Lectures, 4 vols. 1859–61). These lectures, which were mostly written during the currency of the sessions in which they were first delivered, want the exactness of thought and expression which mark the works revised by himself for publication; and it is to be regretted that the materials embodied in these volumes were not wrought into another work which Hamilton had planned. This was his edition of the works of Reid, with notes and supplementary dissertations. The general aim of Hamilton's whole philosophy is, in fact, but the special aim of this edition of Reid (1846; additional notes from Hamilton's MSS. by Mansel, 1862). His conviction was that the philosophy of Common Sense (q.v.) represents the highest reaches of human speculation; and he accordingly sought in his annotations of Reid's writings, as in his independent works, to point out the relation of the Scottish philosophy to the systems of other countries, as well as to translate it into a more scientific expression. His labour on Reid was interrupted by ill-health. By the paralysis of his whole right side, though his mind continued unimpaired, his power of work was seriously curtailed during the later years of his life. He nevertheless produced a new edition of Dugald Stewart's works in 1854-55; and he was generally able, with an assistant, to perform the duties of his class till the close of session 1855-56, when his health suddenly became worse, and he died 6th May.
Hamilton's system professes to be merely an explication of the Scottish philosophy; it may, however, be questioned whether all his exegetical skill has vindicated the position claimed for Reid, whether, therefore, it would not have been better for Hamilton had he struck into a separate path. For while his philosophy is distinguished in general from previous Scottish speculations by its more rigorously systematic character, it ventures, as in his doctrine of the conditioned, into wholly new realms of thought. This doctrine, which limits positive thought to the conditioned sphere between the contradictory poles of the infinite and the absolute, attracted more attention than any of his other doctrines, especially after the publication of Mansel's Bampton Lectures in 1858 (see CONDITION). Hamilton's contributions to logic may be reduced to the two principles (1) of distinguishing reasoning in the quantity of extension from reasoning in that of comprehension, from which issues his twofold determination of major, minor, and middle terms, and of major and minor premises; and (2) of stating explicitly what is thought implicitly; whence were derived the 'quantification of the predicate,' reduction of the modes of conversion to one, and simplifications of the syllogism.
See Life by Veitch (1869); short monographs by Veitch (1882) and Monck (1881); Seth's Scottish Philosophy (new ed. 1890); and SCOTTISH PHILOSOPHY in Vol. IX.