The summary in the video is so bare-bones that I think anyone would be left with questions. The argument is basically that a thing's essence and its existence are not necessarily together -- that is, we can talk about the essences of things that don't exist. For the essence to come into existence requires a cause.
This is from Feser's Aquinas:
And again, it's important that this is a per se series -- acting continually.
So the First Cause has to be something which doesn't exist accidentally, but essentially. That is, its essence is to exist. This would be unique, since everything else has an essence which may or may not exist.
So the Second Way claims to prove that there must be a something of which its essence is to exist, which he claims is necessary for the existence of anything else. As always, this doesn't attempt to prove that the First Cause is the God of the Bible. Only that ontologically, such a cause is necessary.
This is from Feser's Aquinas:
Quote:how does a thing come into existence? That is to say, how is its essence conjoined with an act of existence so that it is made real? “It is impossible,” Aquinas says, “that the act of existing itself be caused by the form or quiddity – and by ‘caused’ I mean as by an efficient cause – for then something would be the cause of itself and produce itself in existence, which is impossible” (DEE 4). In other words, a thing’s essence, form, or quiddity cannot be what brings the thing into existence, for considered by itself an essence is merely potential, and thus cannot cause anything. For an essence to be able to cause something it would first have to be actualized by being conjoined to an act of existing, and that would entail that the thing itself (since it just is a composite of an essence with an act of existing) would already exist. Hence the essence of a thing could cause its existence only if the thing already existed, in which case the thing would in effect be bringing itself into existence, which is incoherent. “It is therefore necessary that everything whose act of existing is other than its nature have its act of existing from another” (DEE 4). But a series of things deriving their acts of existing from something else cannot go on to infinity. Hence “everything which exists through another is reduced to that which exists through itself, as to a first cause” and “there must be something which causes all things to exist, inasmuch as it is subsistent existence alone” (DEE 4). That is, there must be something whose essence and existence are identical, and this we call God.
And again, it's important that this is a per se series -- acting continually.
Quote:a thing must be caused to exist not once for all, but continuously, here and now as well as at the time it first came into being; to use the traditional theological language, it must be conserved in existence from moment to moment. But if what conserves it in existence were something which itself was a composite of essence and existence, then that conserving cause would need to be conserved as well. Insofar as the existence of a thing in whom essence and existence are distinct might involve a series of causes, then, we are once again talking about a causal series ordered per se, and thus (as Aquinas says) a causal series which necessarily depends on a first member which is not conserved by anything, but simply exists. In the nature of the case, this could only be something whose essence and existence are not distinct (and thus in need of being conjoined) but identical.
So the First Cause has to be something which doesn't exist accidentally, but essentially. That is, its essence is to exist. This would be unique, since everything else has an essence which may or may not exist.
So the Second Way claims to prove that there must be a something of which its essence is to exist, which he claims is necessary for the existence of anything else. As always, this doesn't attempt to prove that the First Cause is the God of the Bible. Only that ontologically, such a cause is necessary.
