One of the most eminent Victorian men of science, famous as ‘Darwin’s bulldog’, Huxley made unsystematic forays into philosophy. His writings included ‘The Physical Basis of Life’ (1868), and ‘On the Hypothesis that Animals are Automata’ (1874), a monograph on Hume (1879) and the Romanes lecture Ethics and Evolution (1893). Huxley is credited with the invention of the term ‘agnosticism’.