The Military Genius of Alexander the Great
Alexander [the Great] was a military genius. No other ancient commander was so quick to understand and defeat his enemies’ plans, so quick to analyze a problem and grasp the solution—and, not coincidentally, no other ancient commander was as well educated as Alexander, by the greatest soldier and diplomat of his age, [King] Philip [of Macedon], and by the greatest philosopher, humanist, and scientist of any age, Aristotle. In every aspect of warfare Alexander outthought and outfought his enemies. He enunciated his military objective in the simplest and most forceful terms: he would meet Darius on the battlefield, fight him, and kill him. He forced Darius to react to him, and although Darius and the Persians chose where to fight, Alexander seized the initiative by doing the unexpected—by attacking in the evening instead of the morning at the Granicus or by maneuvering off the prepared battlefield at Gaugamela. He brought together a large enough force to defeat the Persians but kept it small enough to be supplied and to be mobile. As bold as he was in the attack, just so cautious was he in securing his troops against attack. He was the complete commander.
— With Arrow, Sword, and Spear, pp. 273-74