  In 1618, at the age of twenty-two, he enlisted in the army of Prince Maurice of Nassau. It is not known what his duties were exactly, though Baillet suggests that he would have very likely been drawn to what would now be called the Corps of Engineers (Baillet, Livre 1, Chapitre 9, p. 41). This division would have engaged in applied mathematics, designing a variety of structures and machines aimed at protecting and assisting soldiers in battle. Sorell, on the other hand, notes that in Breda, where Descartes was stationed, the army “doubled as military academy for young noblemen on the Continent” (Sorell, p. 6). And, Gaukroger notes that the education of the young noblemen was structured around the educational model of Lipsius (1547–1606), a highly respected Dutch political theorist who received a Jesuit education at Cologne (Gaukroger, pp. 65–6). Although the historical records point to there being a military presence in Breda, there is no definitive evidence that speaks for there being a full-fledged “academy”. There are reasons for thinking that Descartes may have been a soldier, but the majority of biographers suggest that it is more likely that his duties were oriented more toward engineering or education.