In Memoriam

I know how memory works.
Almost twenty years of professing (I know how it works).

Yet there is nothing I know to quantify this:

I had forgotten
    your look
     your laugh
       your name

Until

Your obituary  recalled them all for me.

And, where was

     the blank of years between talking in class until today

now is 

     the sharpness of detail and loss.

(recalled just to lose again)

There is nothing I know to quantify this
(I know how memory works)