De Morgan was born in India, educated at Trinity College, Cambridge, and became first professor of mathematics at the university of London, being appointed to his Chair at the age of 21. He wrote widely on mathematics and astronomy. His Essay on Probabilities (1838), Formal Logic (1847), and Syllabus of a Proposed System of Logic (1860), together with the informal Budget of Paradoxes (1872), represent his work in logic and scientific method. He was a pioneer ahead of his time in the development of formal logic, writing that ‘every science that has thriven has thriven upon its own symbols: logic, the only science which is admitted to have made no improvements in century after century, is the only one which has grown no symbols’. De Morgan was a pioneer in recognizing the close affinities between logic and algebra, in recognizing the importance of a doctrine of predication, and in opening up the logic of relations. He corresponded widely, and was an acknowledged influence on Hamilton and Peirce.