 A simple argument that Avicenna attributes to the advocates of  (PM)  goes as follows: Mathematical objects are separate. In other words,  (SM)  is true. Moreover, the principles (or causes) of material things cannot be themselves material. They must be separate. Therefore, mathematical objects are the principles of material (or, natural) things (Avicenna [MPh]: chap. VII.2, sec. 7). Avicenna thinks that this argument is not only unsound due to the falsity of (SM) but also invalid. Even if we accept both that mathematical objects are separate and that the principles of natural things must be separate, we cannot validly conclude that mathematical objects are the principles of natural things. There might exist other separate non-mathematical things which form the principles of natural beings. The argument in question is valid only if we presuppose that mathematical objects are the only separate existents. But this is something for which we have no proof. Therefore, this argument fails to establish (PM) (Avicenna [MPh]: chap. VII.2, sec. 21; Marmura 2006: 365–66; Porro 2011: 294; Zarepour 2019: sec. 4.2).