Finality causality or teleology is the thesis that natural objects, by nature, act for ends. Understood as such, finality in nature is an essential commitment of any philosopher belonging to the Aristotelian tradition. Aquinas is no exception. In fact, Aquinas seems to stand out in this regard; finality is so central to his system that it even serves as the basis of one of the famous Five Ways he constructed for proving the existence of God, i.e., the Fifth Way. The denial of teleology in nature in that sense, on the other hand, has been an important commitment of philosophers hostile to the Aristotelian tradition. The dialectical exchange between the two camps over this mas’alah is interesting in many ways; one way in particular is what it can reveal about how much they may implicitly concede to their respective opponents. Here I’d like to look at one such (admittedly contrived) exchange by bringing into dialogue two thinkers that come from distinct traditions, one Christian, the other Islamic. The Islamic thinker is Fakhr al-Din Razi (d. 1209), a perceptive critic of the Avicennian (and therefore Aristotelian) system, and the Christian thinker is Aquinas (d. 1274), who is a well-known pillar in the Aristotelian tradition. I’ll proceed in three parts: in part I, I’ll state an objection, which you’re already familiar with from here, that Razi raises against there being teleology in nature. Then, in part II, I’ll try state how I think Aquinas, given the reasoning in the Fifth Way, would’ve responded to that objection. The upshot in part III will be that, in what he does say about teleology in the Fifth Way, Aquinas concedes an important premise of an objection like Razi’s, which has the consequence, arguably, of making finality transcendent as opposed to immanent, which in turn amounts to conceding a conclusion like Razi’s.
I. Razi’s criticism of teleology in nature comes towards the end of his commentary on IV.5, which concerns the nature of the four causes, of Avicenna’s Kitab al-Isharat. It is directed specifically at Avicenna’s thesis, which Aquinas shared, that the final cause is a cause of the causality of the efficient cause. What this means is that the final cause is what causes the efficient cause to be causally efficacious, i.e., productive of effects. E.g., ‘shelter’, as a final cause, moves a carpenter, as an efficient cause, to build a house. At the same time, however, the final cause is also an effect of the efficient cause, which means that if the final cause comes into existence, the cause of its coming-into-being will be the efficient cause. E.g., the house as a place of shelter is the effect of the building activity of the carpenter. This basic point holds in all interactions among natural beings. In sum, and technically put, then, for both Avicenna and Aquinas, in terms of its quiddity – defined as ‘that for the sake of which a thing is’ – the final cause is the cause of the causality of the efficient cause, and in terms of its real existence, it is an effect of the efficient cause.
Razi attempts to raze the above view of the nature of the final cause as applied to inanimate natural substances; in particular, that it’s somehow, in those cases, a cause of the efficient cause. At Sharh al-Isharat (Tehran: Anjuman-e Athar va Mafakhir-e Farhangi, 1383, vol. 2, ed. A.R. Najafzadeh), IV.5, 343, he writes:
Someone might say: There’s a worry in your claim that the final cause is a cause, through its quiddity, of the efficient cause; for you’re trying to introduce the final cause into natural acts and natural potencies that have no deliberation (rawiyah) or awareness (shu’ur) whatsoever. The final cause’s quiddity [in these cases] cannot be said to exist in the mind because there’s neither mind nor awareness here; and [the final cause also] does not exist in the external world because its existence in the external world is the effect of the efficient cause. If this is so, [the final cause] will be an absolute non-existent, and no absolute non-existent can be a cause of an existing entity. So how can the efficient cause be explained by the final cause’s quiddity? The only option is to say natural acts have no ends, but this is contrary […] to the doctrine [of the Aristotelians] […].
Razi’s reasoning for why things without deliberation or awareness have no final causes runs as follows:
- For the final cause to be a cause, it must either exist mentally or extra-mentally
- But in things with no deliberation or awareness, it exists in neither way.
- Therefore, in such things it has no existence at all [from 1, 2]
- What has no existence can’t be a cause
- Therefore, the final cause can’t be a cause in things that don’t have deliberation or awareness [from 3,4]
(1), (2), and (4) are the key premises. Premise (1) is implicit in Razi’s argument and so he does not offer any explicit justification for it. Nonetheless, his point I think is well-founded: he is urging that for something to have any causal efficacy, it must exist, and a thing, if it exists, only does so either in a mind or outside it. There is no tertium quid. Aquinas, it seems to me, would readily concede this premise. How does Razi justify (2)? The thought seems to be: obviously, deliberation and awareness require a mind. So, in things which act without deliberation or awareness, there can be no intra-mental existence of the final cause for the simple reason that such things have no minds. Aquinas rejects panpsychism of any sort, so this point should easily go through by his lights. Neither, though, can the final cause, in such cases, exist outside the mind and somehow be causally efficacious from that vantage point; for “its existence in the outside world is [supposed to be] the effect of the efficient cause.” That is, it does not exist externally yet, because on the present assumption the efficient cause has not yet acted. And with (4), which is taken as self-evident, the conclusion i.e., that “[the final cause] will be an absolute non-existent, and [as such it cannot] be a cause […]” in natural things, follows. Therefore, Razi concludes, there are no ends for which inanimate beings act.
II. How can Thomist resist this conclusion? Ultimately, I think he’ll have to do it by drawing on what Aquinas says about teleology in the Fifth Way. The Fifth Way is meant to be an argument for the existence of God that appeals to the directedness or finality in nature as its point of departure. How is that relevant to answering Razi’s objection? Its relevance consists in Aquinas’ crucial concession, in that argument, that finality ultimately requires intelligence or a mind. The important lines come at I.I.q.2. art. 3 of the Summa Theologica and run as follows (my emphasis):
[…] natural bodies, act for an end, […]. Now whatever lacks intelligence cannot move towards an end, unless it be directed by some being endowed with knowledge and intelligence; as the arrow is shot to its mark by the archer. Therefore some intelligent being exists by whom all natural things are directed to their end; and this being we call God.
Aquinas seems, then, to commit to the view that acting for an end, i.e., finality, requires, in one way or another, intelligence. For “whatever lacks [a mind] cannot move towards an end”, i.e., cannot act teleologically. So a thing, presumably, acts teleologically only if it (A) has a mind of its own or (B) is directed by the mind of another. Natural things don’t satisfy (A), for they lack intelligence or a mind. But they do act for ends. Therefore, they must act for an end due to (B). How the Thomist will respond to Razi’s objection should now be clear: she’ll concede both (1) and (4), but distinguish (2), and thereby deny both (3) and (5). With respect to (1), the requirement that the final causality of a thing presupposes intelligence amounts to saying it needs to exist in the mind of that thing i.e., option (A). And, plausibly, option (B) corresponds to the final causes’ existing extra-mentally, as stated in (2). That is, the way in which a final cause can exist extra-mentally and be efficacious from that point is in the sense captured by (B). With respect to (2), though, Razi, she’ll urge, is partly right and partly wrong: he’s right, insofar as the mental existence of the end is concerned. But he’s wrong insofar as the extra-mental existence of the end is concerned – namely, its existence in an agent with a mind, who imposes that end onto things that have no minds (which just is what it is for their motions to have an end or be goal-directed). And with that, (3) and (5) don’t follow, and so Razi’s objection is disarmed. The response can be recapitulated as follows:
- That for the final cause to be a cause, it must either exist mentally or extra-mentally, is granted
- But in things with no deliberation or awareness, it exists in neither way, is denied; for it exists extra-mentally, i.e., in another agent with a mind
- Therefore, that in such things it has no existence at all, is denied; in such agents, it only has no mental existence
- What has no existence can’t be a cause
- Therefore, that the final cause can’t be a cause in things that don’t have deliberation or awareness i.e., in sense (A), is granted; but that it can’t be a cause in sense (B), is denied
Thus, it’s not the case that things with not deliberation and awareness don’t act for an end.
III. As we’ve seen, the Thomist response to Razi’s objection consisted in effectively conceding that in order for the final cause to be efficacious, it must exist and that it can’t exist apart from some relation to a mind, i.e., either in sense (A) or (B). Further, in order to deny (3) and (5), the Thomist claimed that things that don’t have (A) nevertheless act for an end by means of (B), i.e., their finalities come to them from something external, a separate cognitive agent. What’s the problem with this? Well, it not only concedes a key premise to Razi – that teleology as such requires a mind – but also, arguably, concedes his anti-teleological conclusion, i.e., that final causes are not built into natural things which lack minds, but imposed from without. This is so because it locates such ends in a supernatural agent, i.e., God. God imposes and directs a natural body, we’re told, in the way “the arrow is shot to its mark by the archer”. But the arrow has no built in final cause of moving towards the mark; that end is forced on it from a mindful agent. Razi would balk atIf the Thomist demands that teleology necessarily requires a mind, and models teleology in nature on artifacts, she effectively concedes Razi’s main point, i.e., that it is a supernatural agent, i.e., God, who makes natural agents act or behave in the characteristics ways that they do whenever they do. In that sense, natural substances are just like artifacts – their ends are imposed on them by transcendent mindful agents. Such ends are not immanent in the sense of following upon their essences or what they are in themselves, just as how moving toward a mark is not an end built into a piece of metal but is imposed on it by the archer. Final causality then becomes transcendent affair a la the Platonist, and no longer an immanent one a la the Aristotelian. And given Razi’s other (apparently) Platonist commitments, that would be a conclusion he’d warmly receive. The Thomist, however, ought to find it troubling.