The international debate on the animal machine was initiated by the preface that the Dutch philosopher and later professor of medicine Florentius Schuyl in 1662 added to his Latin translation of Descartes’ Treatise on Man. Schuyl defended the animal machine in reaction to the vehement attacks, mostly in the vernacular, against the philosophy of Descartes in the Dutch Republic in the 1650s, wherein the theory of the animal machine had become one of the flashpoints. These polemics were part of a (...) power struggle, not a quest for philosophical truth. Schuyl focused on the points that had appeared as controversial in these debates: biblical exegesis, arguments from common sense, and to some extent physiology, but ignored wider philosophical questions. Questions about the soul and human uniqueness came to the fore only when his work was picked up in a new context, the international republic of letters. Schuyl's preface is therefore an interesting example of knowledge taking shape by circulation. (shrink)