It has occurred to me that I should make a fine distinction that might clarify many of my posts, especially for those coming from an analytic or continental perspective, e.g., soft/hard scientific naturalism, materialism, variants of OOO, etc.
I have been arguing for a Peircean-derivative triadic view of reality in which possibility, existence/energy/activity, and law or habit are real. To be real is to have real effects, but is not necessarily to exist or have causal power. Possibility and law have no causal power, but then, it depends upon what one means by "causal power."
I will investigate the notion of causal power through adopting an Aristotelian language, which I presume all readers might share. I say that only existence has efficient or material causal power. Possibility cannot be a cause without being actuality, in which case it exists and has causality in virtue of that. Law is not material, and since only material things can act via efficient causality, law has no efficient causality. This follows from Aristotle's views if we momentary omit eros as a kind of efficient causality; recall that the Unmoved Mover had an erotic power akin to efficient causality that caused all the cosmos to move in response. Since possibility has neither material nor efficient causality, does it have formal or final? No. A possibility as a mere possibility is an impulse, a pure spontaneity that in itself is no thing; it does not exist and has no determinacy. Possibility, as firstness, can only have the determinacy necessary for formal or final causality insomuch as it becomes secondness (existence/energy/act) or thirdness (law/habit). Moreover, it becomes these things through temporalizing, and thus even more than the triad is needed to claim that possibility can be formal or final. One might be tempted to dismiss possibility as part of ontology, until I remind them that spontaneity cannot be excluded without likely positing a mechanistic universe. Finally, does law or habit (thirdness) have formal or final causality? YES.
Formal causality understood as identity, i.e., as determinate predication that indicates the composition of a thing is something that can be said of habit (thirdness). However, as previously discussed, there are at least two irreducible kinds of "formal" causation here. There is "form" understood as composition or constitution, and "form" understood as structure. For instance, an imperfect vs. a perfect crystal lattice have the same composition, but might have very different causal properties in virtue of divergent structures. These two kinds of causation are semi-independent, but distinct, and for that we need look no father than ice. Phase change phenomena are excellent examples of the distinction.
Law or habit has final causality, but only if we include time. What is time? For now, I propose that we define time as the asymmetric relativity of (real) relations. In any particular case, temporality describes how an event relates to other events. I have given arguments that the past-to-present and present-to-future relations are not identical, which I mention to complicate on-the-face-of-it readings. Part of the reason that these are different is due to the reality of chance, as possible probability structures for each are non-identical; see the recent posts. In sum, "final causality" as I might use the term is indistinguishable from claiming the reality of purposiveness or emergence in nature. That is, the next event is never reducible to the prior event, and the remainder is not merely attributable to chance. Nature loads the dice, since nature tends towards wholeness, and any case of final causality is just the local instance of wholeness, whether that be a growing plant or crumbling mountain. In contrast, if nature did not tend towards anything in particular, then law or habit would be impossible, because ice could be cold one moment and on fire the next. This might seem like an odd way to view the matter, and the oddity is due to accepting the reality of chance. Once that is accepted, we must explain how the cosmos is not utter chaos.
Why is the cosmos not utter chaos? Why may things tend to wholeness? Why love and eros, of course! I am not thinking of final causality or teleology as mysterious forces pulling something along, which is actually a Platonic and not Aristotelian view.
I do not think it is helpful or instructive to stress law or habit as final causality, and I do it merely as an exercise. It is not instructive because making that connection work draws in too many other principles, e.g., time, purposiveness, wholeness, etc.
I would add one last caveat: history and time are distinct. I think too many misunderstandings occur because when I write "time," people read "history." That is not a problem when one treats time as static progressive process, but since I think it as a dynamicly asymmetric process, then commonsense or typical notions of time--even philosophic ones--miss the mark. For instance, given my limited understanding of McTaggart-type arguments, they are not even compatible with this view of time and the resultant view of history. History is concretized temporality.