Chapter 137 — That some things are said to be by chance and fortuitous

Although all events, even the most trifling, are disposed according to God’s plan, as we have shown, there is nothing to prevent some things from happening by chance or accident. An occurrence may be accidental or fortuitous with respect to a lower cause when an effect not intended is brought about, and yet not be accidental or fortuitous with respect to a higher cause, inasmuch as the effect does not take place apart from the latter’s intention. For example, a master may send two servants to the same place, but in such a way that neither is aware of the mission of the other. Their meeting is accidental so far as each of them is concerned, but not as regards the master.

So, when certain events occur apart from the intention of secondary causes, they are accidental or fortuitous with respect to those causes; and they may be said to be fortuitous simply speaking, because effects are described simply in terms of their proximate causes. But if God’s point of view is considered, they are not fortuitous, but foreseen.