Xenophon,
Anabasis — Book 2, Chapter 4
“ Clearly, the attacking party must either conquer or be worsted: if they conquer, what need of their breaking down the bridge? "Why! if there were half a dozen bridges," said he, "we should not be any the more able to save ourselves by flight--there would be no place to flee to; but, in the opposite case, suppose we win, with the bridge broken down, it is they who will not be able to save themselves by flight; and, what is worse for them, not a single soul will be able to bring them succour from the other side, for all their numbers, since the bridge will be broken down." ”
