Comment by throw0101d

> We as in civilization? We made it at least a few thousand years without it.

Civilization is a continuity of discrete points of time.

We were able to enter (so-called) Dark Ages where things were forgotten (e.g., concrete) and still continue because things were often not very 'advanced': with the decline of Rome there were other stories of knowledge, and with the Black Death society hasn't much beyond blacksmithing and so was able keep those basic skills.

But we're beyond that.

First off, modern society is highly dependent on low-cost energy, and this was kicked off by the Industrial Revolution and easy accessible coal. Coal is much depleted (often needing deeper mines). Then next phase was with oil, and many of the easy deposits have been used up (it used to bubble up to the ground in the US).

So depending on how bad any collapse is, getting things up without easily accessible fossil fuels may be more of challenge.