The Makedonian phalanx -- why such depth?

[MeinPanzer]

As I said, I would not wish to get into yet another digression on the subject of peltasts/thureophoroi, but....
Ruben wrote:

I should first note that I am only working from Asclepiodotus, as I think that his manual is the only one that can be verifiably linked to any true Hellenistic military practice

....it is generally reckoned that all three manuals -Ascepiodotus,Aelian and Arrian are drawing on a common single source - sometimes thought to be Poybius lost section on this subject, but the source is more likely Posidonius. Asclepiodotus is mentioned by Seneca as being a follower of Posidonius, and both Aelian and Arrian refer to him.

But herein lies the clincher for me: Asclepiodotus was almost certainly a pupil of Poseidonius, who was very likely well-acquainted with the Seleucid military, and who drew from his teachings directly. Aelian and Arrian, while they most likely drew from Poseidonius, are fairly far removed from him. Therefore, of the three I think only the details of Asclepiodotus can be trusted. We all know how easily ancient authors relying on sources which were already ancient for them could mix up simple statements or passages. Case in point:

Arrian says:" ....Light troops (psiloi) are the exact opposite in having no body armour,shield,greaves or helmet, but being trained to the use of missiles, arrows, javelins and stones slung or by hand..."

Aelian says:"...on the contrary the light infantry (psiloi) are equipped in the least cumbersome way; they wear neither a coat of mail, nor greaves, nor the heavier kinds of shields; but they use missile weapons, either arrows shot from bows or darts/javelins or else stones thrown from slings or with the hand...."

but elsewhere: "...the equipment of the foot-soldiers is of three kinds - some are completely armed, some just have shields, and some are light-armed troops( psiloi). The completely armed soldiers wear the heaviest armour of all; after the Macedonian manner their shields are round and their pikes are long..."

Where does Arrian get the "no shield or helmet" part from? Why does Aelian state that the psiloi used shields, and yet doesn't mention helmets?

Clearly, these three 'classes' of troops are the broadest of generalisations. All three manuals say that the 'light/ medium' troops carry a shield lighter or smaller than the round shield of the heavy armed, which whilst it may be true of the argive aspis, isn't true of a Macedonian Phalanx who carry a species of pelta !

As elsewhere in his treatise, Asclepiodotus seems to either be missing something in his understanding of Hellenistic infantry or deliberately reorganizing things to suit his idea of what a Hellenistic army should be (like Xenophon's cavalry equipment in On Horsemanship doesn't actually reflect what an Athenian cavalryman of his day would wear). He states on this matter only that the hoplites (phalangites) carried "shields of the largest size," and then goes on to state that the best shield for the phalangite to use is the Macedonian, which was bronze, c. 60 cm in diameter, and shallow. While he describes the pelte, which the peltasts used, as being different from the "shields of the largest size" carried by the phalangites, the Greek does state that phalangites could (and presumably did) use different kinds of shields. Therefore, I think what he means by distinguishing between the shields of the phalangites and those of the peltasts is that the former were heavier because they were faced with bronze (as in the Chalkaspides, Arguraspides, etc.) and could be much bigger (as in the Aemilius Paullus relief, or the Pergamon battle plaque), while the latter were neither. It is perhaps for nothing that the most prominent peltast unit in the Antigonid Macedonian army was distinguished from the Chalkaspides by having white, rather than metallic, shields.

If we follow the manuals broad generalisation of 'light/medium'(peltastoi) as being troops who can skirmish in open order, or, thanks to having shields/helmets/some armour can also fight hand-to-hand ( though not able to withstand heavy-armed infantry) then Thureophoroi fall into this category, and are the natural successors to greek peltasts - the original ones. Which isn't to say that the pelta, if defined as simply 'light shield' had disappeared - it continued in use, no doubt, among other peoples but it appears to have been supplanted by the 'thureos', which also replaces the aspis among Greek mercenaries, so that instead of 'mercenary peltasts' and 'mercenary hoplites' as separate types, we now hear only of 'mistophoroi'(mercenaries) as a single category......

At least from Asclepiodotus, no indication is made of the peltasts being skirmishers - only that they carried lighter shields and shorter spears. I simply cannot take Asclepiodotus' comment, however, that the peltasts are so-called because "the pelte is a kind of small, light shield" as an indication of anything other than that these men carried the pelte proper. It is too explicit to be able to interpret this class as also including thureophoroi.