In my more aggressive moments, I'm inclined to think that the only interesting question in all of philosophy is that of individuation. That there even is a question of individuation is not always recognised though, so I just wanna lay out three approaches to individuation, if for nothing else than just a conversation starter.

(1) Traditionally, the question is structured something like the principle of sufficient reason: what is it that picks this thing out as an individual, and not some other individual? What makes this (individual) the individual thing that it is (and not something else)? If you have a mole on your face and I do not, one can say that the presence or absence of the mole (among other things) individuates us as different individuals.

(2) This, though, isn't a great way to think about individuation. A deeper and more interesting approach is to ask how it is that an individual has become the individual that it is: this is to treat individuation as a process, in which an individual is gradually 'given form' (morpho-genesis) to become the individual that it is. And even here, one can draw distinctions between two further approaches to individuation:

(2A) The first approach treats the individuation of any one thing as a 'given': given that we have an X (a cyclone, a person, a society, a meaning - anything) what are the conditions and/or forces (and/or etc) that brought about the individuation of X? 'X' is here the (individual) subject of the process of individuation: X is what is individuated.

(2B) A second (superior!) approach does not treat the individuation of a entity as a given; rather it treats the fact that there is an individual X at all to be a contingent fact, one that, in different circumstances, might not have come to be at all. In this approach, the subject of individuation ('what' is individuated) is not the individual, but the very process of individuation itself: the individual is an outcome or a 'remainder' of a process which is primary with respect to the individual it engenders.

What is at stake in these ever deepening approaches to individuation is the need to avoid teleology: the idea that the individuation of any entity is a fixed outcome that would be in some sense 'pre-destined' from the very beginning. By treating an already-constituted individual as a given, what is left unexplained iswhy a particular process of individuation took place to begin with. To properly account for individuation, in other words, it is necessary that one does not take for granted the fact that any one individual would be generated at all. The basic lesson of individuation then, is that what must be accounted for is not just how such and such has come into being, but that it has come into being at all.