members but not others, without being a cause of the aggregate as a whole.

Indication:
In any aggregate of causes and effects arranged in succession, an uncaused cause, if present, is an endpoint; for if it were an intermediate member, it would itself be caused.

Indication:
For any ordered chain of causes and effects, whether finite or infinite, it has been shown that if it contains only caused members, it requires a cause external to it. An endpoint of the chain must necessarily be connected to that cause. Thus, if the chain contains something uncaused, it is an endpoint and a terminus. Every chain therefore terminates in that which is necessary in existence in itself.

[Comment on Ibn Sīnā’s words]

I say:
The substance of this discussion is that an existent is either necessary in itself or contingent, existing only through something else, as he established in the two indications. However, it has been said that the discussion contains unnecessary repetition. If a contingent being exists only through something else, it is an effect brought about by a cause. An infinite regress of effects is impossible, because each individual member is contingent, and the aggregate depends upon those contingent beings; it is therefore contingent, not