Qualities Needed In A General

Being who I am, I love to read multiple books at the same time, therefore allowing me to jump from one story to another, or one topic to another, without letting my curiosity wane.

Out of the four books I'm reading now is the historic account 1776 by David McCullough which I find utterly fascinating (especially since I've never studied/read about American history before).

In it, he describes how Nathanael Greene learned about war, which was solely through books and treatises, including that of Marshal Maurice de Saxe's Memoirs Concerning the Art of War, which states that:

"The first of all qualities [of a general] is courage.  Without this, the others are of little value, since they cannot be used.  The second is intelligence, which must be strong and fertile in expedients.  The third is health."

Short, and to the point, and probably something the young Greene (at the time) took to heart when he was made the "youngest general officer in what constituted the American army, and by conventional criterion, an improbable choice for such responsibility."

PS: Just found out General James "Maddog" Mattis, of the Marine Corps, decided to retire.  Now I don't know much about him except from what I've read, but it appears to me he did fulfill these three requirements.  Here's one of his quotes:
"If in order to kill the enemy you have to kill an innocent, don't take the shot.  Don't create more enemies than you take out by some immoral act."