Of course, reapers also, instead of seeing the normal world, could see all the life energy of the world. Everything was completely black, except for white outlines of all solids, and a white mist for anything that has life energy. James could tell how confused Jack was though, and held up a note: 

[I]I am sending my son to this school so he can learn to act like the mortals do.

- Thanatos, A.K.A. Death[/i]