I think that, as part of the clock, a sign should be placed near it that states "not predicting the end of the world."

I can just see the "not" getting removed at some point in history and hijinks ensue.

Won't work. "God is testing our faith!"

The fact that it's dug into a mountain and has multiple large chambers definitely won't help make it seem scientific and not archaic, mysterious and cultish. I swear they are taking cues from novels.

I think Neal Stephenson is actually part of the Long Now. Looks like they lifted something right from Anathem.

Anathem was inspired by the Long Now, not the other way around.

How does a clock that is designed to run for thousands of years with no set stop date predict the end of the world?

You could ask the same question to people who are convinced that the Mayan calendar indicates that 2012 is "the end of the world".

what do you mean hollo documentaries?

we will get back to the stone age between those two things.

In 10,000 years, humans could repeatedly cycle between "Stone Age" and "holo documentaries". Civilization as we know it isn't that old, technological civilization even less so.

I don't have a citation, but I've read that if we fall, we won't get back up. The easily mineable metals, minerals and fuel sources have been used up - starting again from scratch would be incredibly difficult.

(Larry Niven addresses this somewhat in his novel The Mote In God's Eye. I can't really elaborate without spoilers. :P)

OTOH, people could mine already-manufactured stuff from landfills; see World Made by Hand.

Speaking of cyclic history, I also liked "The Peddler's Apprentice".

I wonder how viable that is. In a world where we're considering sucking oil out of sand and stealing air conditioners for $2 worth of copper, I'm surprised there aren't more landfill reclamation projects - so maybe that's strong evidence that landfills don't contain as many goodies as we think.

Plus, you're not going to find coal or oil at a landfill, except in the form of plastic.

For many materials, I think landfill mining is a lot more viable than mining from ores, both on the basis of high concentrations and on the basis of higher energetic states. I mean, you're not going to find native iron, aluminum, titanium, or silicon in rocks, and cullet is a lovely material for making glass from. And, in most of the world, you'll find a lot more platinum and tungsten in the landfill than you will in your local rocks.

Energy and helium are the only resources we're currently consuming. The others are just being reversibly transformed.

Mining landfills is dangerous work, but it can be automated. Mining in general is dangerous work, but I suspect that landfills are even more unpredictable than rocks. Landfills contain smallpox virus, polychlorinated biphenyls, HIV-contaminated hypodermic syringes, and so on.

I think that current landfill mining is limited largely by aesthetic considerations (and the resulting laws), not pure self-interest.

Just like it happened to whatever previously available natural resource they used to build the pyramids? :)