Who is the third who walks always beside you?
When I count, there are only you and I together
But when I look ahead up the white road
There is always another one walking beside you
Gliding wrapt in a brown mantle, hooded
I do not know whether a man or a woman
—But who is that on the other side of you?
—T. S. Eliot, The Waste Land (1922)
This, I think, is an interesting one, because Eliot's modernist warning seems to have echoes of the malevolence that is hidden behind the humour and warmth of Suttree.