Studied at the Scuola Normale Superiore of Pisa with R. De Paolis and in 1891 he graduated under his supervision. Later he went to Roma where he studied with L. Cremona and G. Castelnuovo, and in Torino with C. Segre. He taught geometry in Bologna since 1896 and in Roma (since 1922).

Enriques is universally known as one of the most eminent geometer of Italian school and above all for his results on classification of surfaces in three space, but he was also involved in philosophy (he was also president of the "Società Filosofica Italiana" and co-founder of the influential journal "Scientia") and in educational issues (in 1918 he was elected as president of the Italian society for education in mathematics "Mathesis"). In 1907 he (jointly with F. Severi) was awarded with the prize Bordin of the Academie des Sciences and in the same year he won the prize of the Accademia nazionale dei Lincei. He was also a member of the same Accademia.

Among his many students we cite: U. Amaldi , O. Chisini, L. Campedelli, F. Conforto, G. Franchetta, M. Pompilj, O. Zariski.

His selected papers were published by the U.M.I. since 1956 (ed. Cremonese, Roma).

Main commemorations and studies: G. Castelnuovo, Rend. dell'Acc. Nazionale dei Lincei , (8), 2, 1947, 3-21; F. Conforto, Rend. di Mat. e delle sue applicazioni , (5), 6, 1947, 5-31; L. Godeaux, Bull. de la Soc. R. de Sciences de Liège , 2, 1951, 77-85; L. Campedelli, Periodico di Mat. , (4), 24, 1947, 1-20; AA. VV., Rend. di Mat. e delle sue applicazioni , (5), 16, 1957, 1-22; G. Israel, Dizionario Biografico degli Italiani , Roma, ; C. Eisele, Dictionary of Scientific Biographies , 4, 373-375; AA. VV., Lettera Pristem , 19-20,1996, dossier I-L.

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