John Elliott Cairnes (26 December 1823 – 8 July 1875) was an Irish economist. He is often described as the "last of the classical economists".
John Cairnes was born at Castlebellingham, County Louth. He was the son of William Elliott Cairnes (1787–1863) of Stameen, near Drogheda, and Marianne Woolsey, whose mother was the sister of Sir William Bellingham, 1st Baronet of Castlebellingham. John's father decided upon a business career, against the wishes of his mother (Catherine Moore of Moore Hall, Killinchy), and became a partner in the Woolsey Brewery at Castlebellingham. In 1825, William Cairnes started on his own account in Drogheda, making the Drogheda Brewery an unqualified success. He was remembered for his great business capacity and for the deep interest he took in charity.
After leaving school, John Cairnes spent some years in the counting-house of his father at Drogheda. His tastes, however, lay altogether in the direction of study, and he was permitted to enter Trinity College, Dublin, where he took the degree of BA in 1848, and six years later that of M.A. After passing through the curriculum of Arts, he engaged in the study of Law, and was called to the Irish bar. But he felt no very strong inclination for the legal profession, and during some years he occupied himself to a large extent with contributions to the daily press, treating of the social and economical questions that affected Ireland. He devoted most attention to political economy, which he studied with great thoroughness and care.
While residing in Dublin, he made the acquaintance of Archbishop Whately, who conceived a very high respect for Cairnes' character and abilities. In 1856, a vacancy occurred in the chair of political economy at Dublin, founded by Whately, and Cairnes received the appointment. In accordance with the regulations of the foundation, the lectures of his first year's course were published. The book appeared in 1857 with the title Character and Logical Method of Political Economy. It followed up on and expanded J. S. Mill's treatment in the Essays on some Unsettled Questions in Political Economy, and formed an admirable introduction to the study of economics as a science. In it the author's peculiar powers of thought and expression are displayed to the best advantage. Logical exactness, precision of language, and firm grasp of the true nature of economic facts, are the qualities characteristic of this as of all his other works. If the book had done nothing more, it would still have conferred inestimable benefit on political economists by its clear exposition of the true nature and meaning of the ambiguous term law. To the view of the province and method of political economy expounded in this early work the author always remained true, and several of his later essays, such as those on Political Economy and Land, Political Economy and Laissez-Faire, are but reiterations of the same doctrine. His next contribution to economical science was a series of articles on the gold question, published partly in Fraser's Magazine, in which the probable consequences of the increased supply of gold attendant on the Australian and Californian gold discoveries were analysed with great skill and ability. And a critical article on M. Chevaliers' work, On the Probable Fall in the Value of Gold, appeared in the Edinburgh Review for July 1860.