[beat]

Truly timeless is a very difficult thing (see the work by the Long Now Foundation for more on that). But I don't think that detracts from the point that these cathedrals were designed to last forever, from the perspective of the designers - the Notre Dame is 856 years old. It took about a century just to build it. It was epic, and clearly, it still is.

Who builds a building like that today? Other than the Long Now's clock, who is really building things designed to last for centuries, millennia? That's my point. Even the most epic of modern architecture generally isn't thinking beyond a century or so. Hell, my house is over 100 years old. So modern materials thinking, in its usual box, is not really up to the task of re-roofing Notre Dame in the way it deserves.

That doesn't mean we can't do it, or we should just build another flammable wooden roof. But it does mean that we need to think about how it should be done, to protect and preserve the legacy of that historic triumph of the human spirit over time itself.

If you're worried about true timelessness... even the pyramids will die someday, eaten by the relentless desert sands. But we can maybe make something that lasts as long as human civilization itself, if we try.

[yourduskquibble]

One could argue that we do have moderm day timelessness; single use plastics that will take a few thousand years to be destroyed.

[beat]

Eh. I'm talking about things we intend to keep in their current structure. Getting all negative about trash is kinda boring, really.

Given a reasonable extension of existing technology, we could eliminate that trash eventually. Imagine, say, machines designed to find plastic trash in the ocean, powered by ocean currents/thermals, that decompose the trash into basic releasable organics like CO2 and water. Just takes the will to do it. And hopefully someday, that will will exist.

And cleaning up the wreckage of the Industrial Revolution for the sake of future generations would be a legacy we could be proud of.