Ono No Komachi, a poem

I sometimes read something--an aphorism, a part of a novel, someone's comment, or a poem-- that causes me to stop and reread it again, and sometimes several times. Frequently I don't know why that particular utterance intrigues me, and sometimes I'm not even sure what it means. But, it happens, and this poem is one that caused me to halt when I read it yesterday. And, I'm not even sure of what it means. Perhaps it's an illustration of the last lines of Archibald MacLeish's "Ars Poetica"

A poem should not mean
But be.



Perhaps. But here is the poem, a short one:

A thing which fades
With no outward sign--
Is the flower
Of the heart of man
In this world!

-- Ono No Komachi --
from The World's Best Poems
Mark van Doran and Garibaldi M. Lapolla, eds.


Is the poet sad here, or resigned?