With regard to body, Cordemoy warns that we must be careful to avoid the mistake made by other Cartesians, who have conflated what are in fact two distinct things, namely, ‘bodies’ and ‘matter’. The former are, according to Cordemoy, the true extended substances, while the latter are assemblages, or collections, of the former. The key point is that as substances, bodies must be simple: if bodies had parts, they would depend on those parts to be what they are, and in this way the parts would thre