“Do identity and distinctness facts threaten the PSR?”

One conception of the Principle of Sufficient Reason (PSR) maintains that every fact is metaphysically explained. There are different ways to challenge this version of the PSR; one type of challenge involves pinpointing a specific set of facts that resist metaphysical explanation. Certain identity and distinctness facts seem to constitute such a set. For example, we can imagine a scenario in which we have two qualitatively identical spheres, Castor and Pollux. Castor is distinct from Pollux but it is unclear what could metaphysically explain this distinctness fact. In this paper, I argue that we should not treat identity and distinctness facts as metaphysically fundamental. As such, identity and distinctness facts do not challenge the PSR. We can metaphysically explain them.