Earnest Bunbury:
The objection I proposed to Aquinas’ first way was that it begged the question: it assumes that the series in question needs a first cause in order to demonstrate that it has one. That is, it assumes the series is finite in order to show that it isn’t infinite.
In response to this objection, I can only discern two replies in your post.
…(cut, EB)
To (ii):
As Fergus Kerr notes in
After Aquinas: Versions of Thomism, the five ways have many different powerful and persuasive interpretations. He notes, frequently, that the neo-thomist’s have introduced new readings of the arguments utilizing metaphysical principles. This is contrasted by the French interpretation heralded by theologians like the Jesuits Marcel Chossat (1862–1926) and Henri de Lubac (1896-1991). The prestigious
Dictionnaire de Théologie Catholique describes this position clearly:
“As for the argument of the prime mover such as Saint Thomas understood it, it is a long time since it has been taught, even in the Thomist camp. . . If the argument is taken in the sense in which Saint Thomas borrowed it historically from the Arabs, it is not conclusive, and the criticism offered by Scotus is decisive . . . The Neo-Thomists, by adverting to metaphysical considerations . . . actually abandon the physical argument of the prime mover, just as do all the other members of the Thomistic school . . . [The argument has only] survived in the ranks of Protestant scholasticism, among certain philosophers and well-intentioned apologists’.” -
Dictionnaire de Théologie Catholique, vol. 4 (Paris: Letouzet et Ané, 1939): col. 932–5. As cited by Fergus Kerr,
After Aquinas: Versions of Thomism. Malden (Ma.): Blackwell, 2008. p. 53.
So, I don’t think it’s at all clear that Aquinas was talking about essential causation. But, no matter. You can just make a new argument specifying the causation as essential. Does this rebut my objection? No.
Why? Because you’re
still begging the question: assuming the series is such that it requires a first cause in order to demonstrate that it has a first cause.
You make the claim that the series requires a first cause (or unmoved mover) several times:
And why does this series require an unmoved mover?
Because. If it didn’t, then
That’s it. That’s the only reason you provided for thinking the series requires an unmoved mover. But this is
precisely what I’m objecting to. So you’ve merely repeated the argument I’m objecting to, in response to my objection. Why can’t the series regress infinitely? Because, then, it wouldn’t have an unmoved mover! Of course it wouldn’t.
As Sobel says:
“[T]he First Way is vulnerable to the apparent possibility of self-moving things that have always been in motion, for Aquinas’s premise that “whatever is moved is moved by another” (ST I q2,a3 p. 22), is presumably meant to be a statement of strict metaphysical necessity. But it seems that at least things in perpetual motion could be self-movers. It seems, in Aquinas’s Aristotelian terms, that they could be at every moment things actually in motion and potentially in motion in the immediate future, their changing potentialities being continuously actualized by the action of their immediately antecedent actualities. This conception of a self-moving perpetual mover does not involve its being “in the same respect and in the same way…both mover and moved” (ST I q2,a3, p. 22).” - Sobel, Jordan Howard.
Logic and Theism: Arguments for and against Beliefs in God. Cambridge
To say that neo-Thomists have changed the argument to essential causation inconsistent with Aquinas’ thought is silly, as demonstrated in the conclusion that he was obviously “question begging”. The Church would not ground the understanding of Her theology on such a philosophy this dubious. The view of Aquinas as being this superficial in his philosophical arguments is an indictment of the philosophy the opposes it.
Aquinas’ First Way refers only to essential series in nature, and not to accidental series.
This is Aquinas’ First Way: