Note 201 — Chapter I · (continued 2)

Thomas (Eloge, in Œuvres de Descartes, vol. i. p. 32) says, ‘cet instrument, c'est Descartes qui l'a créé; c'est l'application de l'algèbre à la géométrie.’ And this, in the highest sense, is strictly true; for although Vieta and two or three others in the sixteenth century had anticipated this step, we owe entirely to Descartes the magnificent discovery of the possibility of applying algebra to the geometry of curves, he being undoubtedly the first who expressed them by algebraic equations. See Montucla, Hist. des Mathémat. vol. i. pp. 704, 705, vol. ii. p. 120, vol. iii. p. 64.