I think so. As times and cultures change, what we value changes. So, a poem that could be about a very meaningful topic (let's say beer) in one culture could have much less meaning for a culture that came much later afterwards when beer was a common commodity.

I think it comes down at least partially to taste though. For instance I'm not fond of the aggressive meter and rhyme in this poem Gather Ye Rosebuds but I acknowledge that it's good writing and for the time was probably pretty great.

Or what about these poems by Porchia - they're basically aphorisms, one line each. What makes them poems and not statements? (Besides the opinion of the old white guys running Poetry Magazine, of course.) Is it a poem because the artist defines it as a poem? That ties back into what thenewgreen was saying about blank pieces of paper and intention, I think.

I don't know if it is possible for something to lose a state of existence that it used to have. Certainly not if you are looking at it from an anthropological perspective (she says, having never taken an Anthro class). (And again, we're talking about art here, not like radioactive isotopes with half-lives and decay, etc.) Cave paintings are still art, right, even if they're not exactly in vogue anymore? When there is no more paint on that cave wall, then it ceases to become a painting...but until then that's what it is, regardless of quality, prevailing taste, etc. I would like to draw a parallel and say that I imagine writing and poetry is similar.

But if you disagree I would love to hear your side.