Deleuze says that sensibility is privileged above the other faculties because for it, what forces it to operate is also what it experiences. Its outside is the same as its inside, so to speak.
Im actually not sure I understand what he means. Isn't an objective quantum of intensity different from the way the quantum feels? It seems he is trying to deny this - proposing that the objective quantum is a mathematical abstraction, and the real phenomenon that it measures is sense/intensity/difference, which is only insofar as it is felt.
The categorial human affects like sadness, anger, etc. and the world of entities in space and time that they relate to are all constructed by and on top of a subterranean world of pure intensity.
My understanding is that this is a perfectly defensible theory, at least when it comes to human and animal experience. We don't really know what affect is, but Dan Siegel has proposed that affect drives all cognition. It "motivates" the flow of information, the creation an dissolution of states, the retrieval of memory and so on.
This would mean that even inorganic systems like computer networks and ecological systems literally feel parts of the spectrum of what we are able to feel.
It is not clear to me whether this would extend to the atomic and astrological scales.
What does this discussion have to do with cosmogony? Deleuze defines a world as a sphere of 'common sense' where the faculties are in agreement, such that objects and relations arise. This the sphere of representation, consensus, 'reality' in a quasi-pejorative sense.
Cosmogony is the contemplation of world-birth, so Deleuze's account of the rise of representation out of the flux of difference can be said to be a cosmogonical theory.
The difficulty with it, though, is its immanentism. If every kind of world arises from the sea of difference in basically the same way, then philosophy, religion and science are all basically forms of art - which is the same as nature.
If we accept this, then we've elided the question we started with. We ask: why is there a world, and why are things going badly? Deleuze answers, because differentials yield essences. But then we can ask: why do differentials yield essences? Do they need to? Has it always been like that?
In other words, the answer isn't entirely sincere. It is a sort of creation, a story, a guess. But we want an answer.
The attraction of Meillassioux's principle of factiality is that it is presented as a proof. It must be true, and true once and for all