Post Civilization Syndrome, or PCS, is usually known by a more familiar-sounding, cosier synonym: Individuality.
This is a condition in which the larger picture is lost, in favour of the very small picture of oneself as the whole point of being alive.
This could be seen as personal survival.
It is sensible to have some idea of what the term 'civilization' actually refers to. Here is how I see it:
Civilization is the result of individuals banding together into a large group, to better ensure personal survival.
It can only occur under certain conditions, one of which is the ability to place oneself further down the hierarchy than the larger group.
This may initially suggest socialism, but it is very different.
Socialism is actually many individuals placing themselves, individually, at the top of the hierarchy, under the impression that they are the larger picture, and that 'civilization' is really all about them.
But civilization is an abstract idea, from which individuals give up some of their personal autonomy in favour of an It, which is larger and more enduring than them.
PCS is what afflicts those who exist inside a formerly civilized society, while they unknowingly tear it down with their every thought and action. It is a return to a pre-civilization 'me-first' mentality, while still using up the riches gained from civilization. Logically, there is a limit to how long this can go on, with none of an ex-civilization's members actively contributing anything to it.
It is interesting to note how few people seem able to understand any of this. Which is a prime indicator of just how many suffer from PCS.