that involves existence, then that existence must have a cause. If its cause were complete and it were receptive, no nonexistence would enter into it. For when the cause is complete and the recipient is receptive, the effect must exist. Wherever nonexistence occurs in it, this is due to something lacking in the cause or in the recipient; it is therefore not pure existence.

It thus becomes clear that wherever a cause fails to produce its effect, if this is because a condition is missing, that is a nonexistence. If it is because an impediment exists, that impediment only becomes an impediment because of the cause’s weakness—which, again, is the absence of its strength and completeness. Thus, existence is not the cause of pure nonexistence. This also clarifies the fourfold division: pure existence can only be good.

This is further explained by the fact that every evil in the world falls into one of two categories: either pain or a cause of pain. Causes of pain include evil deeds that entail punishment. Pain that actually exists arises only from some kind of nonexistence, as when it is caused by a disruption of continuity. This disruption is the absence of the cohesion and connection between the two, and that is the evil and corruption.

As for the cause of pain, I have established in a “lengthy treatise” that the root of sins is the failure to fulfil obligations, not the commission of prohibited acts, and that prohibited acts are committed only because obligations have not been fulfilled. Thus, the root of sins is the failure to fulfil obligations, and the root of pain