More word play! Solve (or unsolved, as in a "code")/ dissolve (or not, as in "insoluble")/ absolve. Absolution and absoluteness are still present, of course. I like the new addition of "unobserved", as "unseen" to me also has the implication of "unlit", or "lightless" - what remains in the dark cannot be seen.I would think that "slide" is a lesser form of "sluice", though... and it also does not convey the sense of fluidness quite as much.
Very good poem! So if these are life stages when do poems die? Bad readings?