John Stuart Mackenzie (1860–1935) was a British philosopher, born near Glasgow, and educated at Glasgow, Cambridge, and Berlin. In 1884-89 he was a fellow at Edinburgh and from 1890 to 1896 fellow of Trinity College, Cambridge. He lectured on political economy at Owens College, Manchester, in 1890-93, and in 1895 became professor of logic and philosophy in University College, Cardiff. Mackenzie was a Hegelian of the type of Green, Bosanquet, and Caird.
John Stuart MacKenzie was born the second son of John Mackenzie and Janet Brown on 29 February 1860 at Springburn, near Hogganfield, Glasgow. When he was eight years old, his father decided to take the family to seek their fortune in Buenos Aires. Soon after their arrival, having spent seven weeks at sea, Mrs Mackenzie died of cholera, and Mr. Mackenzie some weeks later. The two boys were sent back to Tollcross to be cared for by an aunt, attended the local school, and then Annfield House Academy, Glasgow. Mackenzie's elder brother went into engineering, while John entered the High School of Glasgow.
He became interested in Descartes, Darwin, Huxley, John Tyndall and Herbert Spencer and thus went on to study Philosophy at Glasgow University in 1977 studying under and befriending Edward Caird and Caird's assistant Henry Jones. Having become particularly interested in German philosophy, he undertook further studies in Berlin. On completing his degree, Mackenzie won the Clarke fellowship and succeeded Jones as Caird's assistant. In 1886, encouraged by his friend W.R. Sorley, he began to study in Cambridge, where he became a close friend of J. M. E. McTaggart who introduced him to the philosophy of Hegel.