Cramer, Gabriel (1704-1752)

Swiss mathematician who introduced Cramer's rule 1750, a method for the solution of linear equations which revived interest in the use of determinants; Cramer's paradox; and the concept of utility in mathematics. Cramer was born and educated in Geneva, where from the age of 20 he was professor of mathematics at the Académie de la Rive. In 1750 he was made professor of philosophy. Cramer travelled in Europe and met leading mathematicians. Cramer's paradox revolves around a theorem formulated by Scottish mathematician Colin Maclaurin, who stated that two different cubic curves intersect at nine points. Cramer pointed out that the definition of a cubic curve - a single curve - is that it is determined itself by nine points. Cramer's concept of utility now provides a connection between the theory of probability and mathematical economics. His major work is Introduction à l'analyse des lignes courbes algébriques 1750, in which he set out Cramer's rule.