Grantaire gestures politely with his bottle: after you.

"Fortunately, one man here -- alas, but only one! -- is a man of noted vigor and direction. As for myself, I am, as we know, gifted with legs, and, granted an aim, shall employ them."

(He doesn't bother to ask for further details on what Bossuet might or might not have said about the multiplicity of worlds involved in ... wherever they are. Apparently he's missed some relevant context, but in a place like Milliways, when has context ever helped to make sense of anything? If that's the aim, alcohol tends to work much better.)