Past thought remains alive

I'd noticed this before, engraved into the paving at the entrance to the Edinburgh University library, but never stopped and paid attention till today. This is one of those poems that can start at a few places in the circle and it still makes sense:

Past thought remains alive.
Interweaved with books our reading becomes a remembrance.

Our reading becomes a remembrance.
Past thought remains alive interweaved with books.

Alive, interweaved with books, our reading becomes a remembrance.
Past thought remains.

Isn't that lovely?

[less lovely is that, as expected, yesterday's trees are now horizontal and being chopped up :(]