so its existence in external reality requires the existence of the spatial locus in external reality,’ we reply: this is disproved by knowledge. Knowledge is a relation, or involves a relation, between the knower and the known. Yet through it we know impossible things, which have no existence in themselves, even though the relation called knowledge actually exists. We thus know that the existence of a relation does not require the existence of each of its two terms.”

In his Nihāya, at the conclusion of this argument, he said: “Know that this argument rests on the possibility of every body leaving its spatial locus. We have already demonstrated this, and it can also be established in other ways. One is to say: if two bodies necessarily occupied a spatial locus, then the locus occupied by the other body would either differ from the first locus or not. If it differed from it, it would be a positive reality, because no difference is conceivable within sheer nonexistence and pure negation. For what is understood by difference is that the reality of one does not stand in place of the other reality. This requires realities that are determinate in themselves, which is impossible in nonexistence. Since that has been ruled out, it is established that if spatial loci were