The Makedonian phalanx -- why such depth?

[Paralus]

Before we go any further, I should note that I don’t – inherently – find anything wrong with files filling space to “close up”. I just don’t think there is enough evidence to hang my gonads on it.

...I did not mean to imply it was the only possible way, though it is the only way we know of for the earlier Hoplite period. It should be remembered that Aelian/Asclepiodotus/Arrian or rather their common source was writing of the Hellenistic phalanx in it's final and most sophisticated form, and the most complex drills devised....

I disagree with the notion expressed in the last sentence. Polybios makes great play of the phalanx’s vulnerabilities and drawbacks and seeks to explain the Greek loss to Rome. Put simply, he describes its charge as irresistible as long as it maintains integrity. That, he avers, is impossible on anything other than cleared level ground. Off such ground it is want to fall apart. As well, he states it is only good for the charge and only in the one direction; it cannot manoeuvrer due to its pikes nor cannot it defend itself if breached in any fashion. It cannot disengage and face about and it most certainly cannot cope with creeks or rivers.

Cynoscephalae and Pydna ‘prove’ his argument (whether by design or not – the descriptions of both are his ultimately).

Despite Polybios’ derision of Kallisthenes, and unless the historical tradition which has come down to us is worth nought, Alexander’s phalanx demonstrably coped with all of the above. If Polybios is to be believed, the Hellenistic phalanxes of Philip V and Perseus were nothing near as skilled or flexible as that which Philip II bequeathed Alexander.

It is difficult to see that which Polybios describes performing the show at Pelium.

Cynoscephalae, in 197 BC against the Romans is one of the last battles of the Hellenistic Phalanx, and significantly is the only battle ( that I can recall off the top of my head), where such lateral movement is described, and in this instance it is for a very specific reason, namely that the Right half of the Phalanx occupied a ridge line ( the Ground of Tactical Importance) until the Left half of the Phalanx came up, then closed up laterally to make room for the left half.....

This highly risky manouevre was carried out with the Romans a considerable distance away, somewhere at the foot of the ridge, and with a peltast screen in place to cover it. It can be regarded as the 'exception which proves the rule'

I shall have to go look for more! In any case that leaves it, in a sense, one all.

Here the phalanx is definitely ordered to double its depth and close up…to the right. The “peltasts” referred to are part of the phalanx and not a screen – both are ordered to close up to the right. The light infantry, from memory, are engaged below and that which is not is deployed on the phalanx’s wings rather than in front.

The question is: why if the rest of the phalanx is still coming up from camp does Philip order this? So as to deliver a charge. Polybios also notes, in passing, that this wing was successful as they were “superior in the weight of their formation”.