French philosopher and logician. Born 1868. Died 1914.

Couturat, influenced by Leibniz, worked mainly with the concept of the infinite. In contradiction of contemporary thought, his work L'Infinie mathématique (1896) argues that there must be an actual, and not merely a possible, infinite.

His interest in Leibniz also led Couturat to edit and publish a number of hitherto-unpublished writings by Leibniz.

Further paying tribute to Leibniz, Couturat devoted a large part of his life to continuing Leibniz' thoughts on the subject of universal language, and to the creation of such a language, Ido. He founded the journal Progreso, which was published entirely in Ido. After Couturat's death, however, Ido was "overrun" by Esperanto, and the language is today more or less defunct.