The Genius of Alexander

Being on vacation means time for some purely self-indulgent reading. I found a free book in a book swap cabinet on great battles, and began with the earliest, the Battle of Arbela, or Gaugamela, by which Alexander the Great conquered Persia.

It quickly becomes clear why Alexander was so Great. He was a great psychologist. He won this battle through superior insight into the psychology of his opponent. He could predict what Darius would do in any given situation, and through this could control him like a puppet.

Alexander understood that Darius was a very cautious, even a timid man. Pulling up his own exhausted forces after a thousand-mile march, facing a vastly superior force arrayed for defense on a battlefield of their choosing, Alexander therefore nonchalantly rested his army for four full days. He understood that he would not be attacked by the Persians; so there was no need to rush into battle with tired troops. Even better, he knew that, meanwhile, the Persians would not be able to rest, Alexander being by no means so predictable, and would thereby be exhausted from lack of sleep by the time he faced them.

Reputedly, the night before the battle, Alexander slept like a baby, and had to be roused late in the morning.

How did Alexander know he would not be attacked? Because the Persians had a vast advantage, in numbers and in having chosen the battlefield. So long as they kept everything predictable, they should have had no problem defeating him. To break up their formations to attack the Greeks first would be to risk losing this advantage; it was like rolling the dice.

Conversely, though, the Persians had to fear that Alexander might indeed choose to gamble, being at a disadvantage, and try attacking them at night; so they could not let down their guard over the four days.

The day before the battle, Alexander led his entire army up the hills surrounding the battlefield, and let them get a good look at the huge Persian army spread out on the plain below them. Wasn't this foolish? Wouldn't it frighten and intimidate his men to see in advance just how much bigger the Persian army was, and how well-chosen their ground?

No; Alexander understood the psychology. Everyone is less afraid of the known than of the unknown. Had he not done this, the Persian opponent would have remained semi-mythical, and might easily have assumed supernatural proportions in the mind's eye. Letting his army all see for themselves, he brought the Persians, formidable as they were, down to the puny dimensions of the real world. Even better, he gave his soldiers an image from above, an image of dominance, the Persians in perspective seeming tiny, like ants. Meanwhile, the Persians, seeing the Greeks watching them from above, and not being able to see their real numbers, probably lost some of their confidence.

Alexander's generals advised him to attack at night, under cover of darkness. This was the classic tactic for an outnumbered army; the idea was that the darkness allowed more surprise, and so favoured an attacker. Alexander refused, saying he "would not steal his victory."Seems reckless and arrogant, doesn't it?

Not at all. Again, this was psychologically wise, and for Alexander the psychology mattered more than the purely military considerations. Had he gained his victory essentially by stealth, by attacking at night, the Persian army, even if technically defeated, would not have felt beaten. They would probably be able to withdraw in reasonable order, even aided by the darkness, and regroup to fight later.

Any war of attrition was certain to go against the Greeks in time--with their smaller forces, smaller population, poorer home economy, and longer supply lines. Only a decisive, demoralizing defeat would win the war. This is exactly what Darius was offering him, by massing all his armies together on a ground of his own choosing.

Alexander, having much smaller forces, was vulnerable to the classic tactic: encirclement of his flanks. This was good, in a way, because he could more or less count on this, and so was again able to predict Darius's actions. The only risk was this: Alexander's Greek phalanxes were extremely strong in defense, and offense is always riskier than defense. The danger was that Darius would refuse to attack, even given the great odds in his favour, and simply wait to fend off the Greeks. That would be the cautious approach. Alexander therefore had to force him into attacking.

He did this by advancing his whole army obliquely. Instead of aiming at the centre of the Persian line, he marched the centre of his army over towards the Persian left flank. This meant that, if Darius did nothing, Alexander would force the battle off of the prepared field, wrecking Darius's battle plans. It would also mean, if he did nothing, that Darius would soon no longer be able to outflank Alexander on the Persian left--again ruining his predicted battle plan. Alexander was forcing him into committing his forces in a certain way. Darius was forced to pull forces away from the centre of his line, and rush them over to the left flank, to keep from being outflanked and to halt the Greek movement. This left the centre weak.

At the same time, in making this feint over to his right, Alexander was also offering an incredibly tempting target--a perfectly exposed Greek left flank, which looked as if it could now be easily turned by the Persian cavalry on the Persian right. To make the prize more tempting, Alexander held back both flanks at a 45 degree angle, making his line appear shorter than it was, and concealing the true strength of his flanks. At the same time, at this angle, they were already prepared to face an attempted flanking movement.

This ensured that Darius would not pull any troops away from the Persian right flank in order to make up for the depletion of the centre. If anything, he was likely to move some further troops from the centre out to the left in order to exploit this opening.

Darius took the bait. He shifted soldiers from the centre out to both the right and left flanks, and ordered the cavalry to charge on his left flank, to stop the Greek advance.

This was the tricky part--it was entirely possible, just here, that the Persian cavalry charges might indeed turn the Greek flanks. Alexander had tactics ready to make this less likely, though. He sent out his own cavalry counter-charges, which then stopped, turned, and apparently fled in the face of the oncoming enemy. It was play acting; seeing their enemy apparently in full retreat, the Persian riders spurred on at top speed, breaking formation, and now psychologically unprepared to face any sudden opposition.

Behind this cavalry screen, Alexander had his phalanxes move forward, so that the Persian cavalry came upon them unexpectedly, in headlong charge. So far, so good--the element of surprise is gained, an important psychological advantage. But Alexander also exploited the psychology of horses, now predictably being given more or less free rein by their riders. As the horses approached, the front lines parted to the right and the left for them. The horses, naturally enough, headed straight for these gaps in the line, instead of running into the outstretched pikes everywhere else.

Each horse and rider was now trapped in a box, where they could be attacked from three sides.

It was enough; given that, according to Alexander's plan, all that his flanks really had to do was to hold off the Persian assault for a certain length of time. Importantly, Alexander had extended the Persian lines, leaving the Persian centre depleted; and he had forced the flanks to be committed, so that they could no longer be pulled back to the centre. This had created his opportunity. He now wheeled his own cavalry, still not engaged after their faked retreat, all over on his right flank, and charged with them in toward the centre of the Persian line.

He did not actually need to break through--all he needed was the psychological shock of seeming close to threatening Darius personally, standing behind the centre of his line. Seeing the danger of personal capture, despite an overwhelming majority in arms, what would a sensible, cautious man do? Of course--get away as quickly as possible. One must live to fight another day, surely? Darius sensibly grabbed a horse and rode for the rear.

But Alexander was counting, yet again, on the psychological effect. As Alexander understood, the Persian army was not held together by any national feeling or great loyalty to their regime, or personal love of Darius; they were a very mixed body of tributary peoples and mercenaries, held together only by the regime's prestige and aura of power. Crack that, and the collapse comes quickly.

Seeing their leader flee the battle caused the Persian resistance to crumble fairly quickly, despite still having numerical superiority over the Greeks.

Interestingly, Alexander did not even bother to hotly pursue. Simply killing more Persian soldiers would not have been of much value. The Gordian knot had already been unpicked.

A few days later, having been exposed as a mere mortal, Darius was murdered by his own retinue.

Alexander had only to pick the crown of Persia up from the dust.

The lessons to be learned from his example here are endless.