by W. S. Merwin
When it is time I follow the black dog
into the darkness that is the mind of day
I can see nothing but the black dog
the dog I know going ahead of me
not looking back oh it is the black dog
I trust now in my turn after the years
when I had all the trust of the black dog
through an age of brightness and through shadow
on into the blindness of the black dog
where the rooms of the dark were already known
and had no fear in them for the black dog
leading me carefully up the blind stairs.
from: The Shadow of Sirius.