 It is but a small step from some of Bolzano’s rather traditional metaphysical views into the realm of the philosophy of nature and of physics. Bolzano introduces a force of attraction among substances (Bolzano 1827, 48) and later also a force of repulsion (Bolzano 1851, reprint 1975: 121, 123 f., E: Russ 2004, 671 f., 673). For the force of attraction Bolzano attempts to prove the Newtonian law that it is inversely proportional to the square of the distance (Bolzano 1827, 50, Bolzano 1851, reprint 1975: 121 f., E: Russ 2004, 671 f.), and further that the force of attraction of two substances is related proportionally to the set (i.e., presumably, to the product of the numbers) of atoms contained in these substances.