It is known that the figures related to casualties in WWI are not completely precise. Statistics vary to a great extent; with numbers that go from 9 million to over 15 million total deaths. These numbers include combat related deaths, accidents, disease and imprisonment related deaths, as well as civilian deaths.
In the excerpt, the narrator gives a real life picture of what war is, how the deceased are not just bodies but human beings: "above such shattered bodies there are still human faces in which life goes its daily roun". He/she questions people's ability to put such slaughter into numbers, as if deaths were no more than that. Thus, this idea becomes clear when the narrator puts the controversy of such act into words: "how senseless is everything that can ever be written, done, or thought when such things are possible".