Synesius of Cyrene (c.370-c.413) was a Neo-Platonic philosopher who became bishop of Ptolemais in the Cyrenaica. He left behind a small corpus of texts that offer much information about daily life in Late Antiquity, and about the christianization of the Roman world.
The Eulogy of Baldness shows Synesius' lighter side: he defends his baldness against the speech In Praise of Hair by the sophist-philosopher Dio Chrysostom ("tongue of gold").
The text is offered here in the translation by A. Fitzgerald. The green four-digit numbers are page numbers of the Migne edition.
The most intelligent of all people, the philosophers, are all bald
  You may look at the pictures in the Museum, I mean those of Diogenes and Socrates, and whomsoever you please of those who in their age were wise, and your survey would be an inspection of bald heads.
 Let not Apollonius confuse the argument, or anyone who was a wizard and an adept in demoniac practices. For although such men are not really adorned with hair, they are able to appear so by gaining a power over the masses of mankind. But perhaps the faculty of these wizards is not knowledge,  but some capacity to work miracles, and is not any sort of science but rather a power. For thus it was that while legislators regarded wisdom as one of the things most to be honored, they kept hangmen to deal with wizards; so that even if Apollonius did become bedecked with hair, this has no bearing on my argument. Moreover, I am kindly disposed to this man and would like to include him in my catalogue. But from what has been said, the argument seems to admit of the converse with soundness. If anyone is wise he is also bald, and if he is not bald, neither is he wise.
 And thus it is with demons also, as he who has seen the ceremonies of Bacchus will agree. As much of the company as is shaggy is adorned, some with their own hair, and others with borrowed locks, for nothing is so proper to Bacchus as the goatskin; and some of them borrow their hair even from pine trees. One has seen them all shaking themselves and reveling, mayhap overcome in their disorderly leaping dances by wine, whatever wine enters at any time into the initiations; yet they seem to have been reduced to the discordant phase of nature.
 There too is the chair of Silenus and his lash. He has been appointed the guardian slave of Dionysus. For I think that, being bald, he must have been also a man of sense, to keep his self-control in the midst of such aberrations. Yet I deem it no small matter that he should be preferred by Zeus to all the demons, with a view of attending upon and teaching his little son wisdom.
 For Dionysus has also to taste the pure juice of the grape and to rave at times with natural desire and approach the point of madness, until finally he joins the Bacchic women in dances. But Silenus moderates his madness lest, oft-times unconsciously, he run wild in both directions, lest he become too difficult for his father to bring up.
 But we must speedily come back to our point, having obtained adequate proof that brains are there whenever hair has taken its departure, and that hair is there where brains have taken their departure.
 Socrates, the son of Sophroniscus, a moderate man in other respects and beyond anyone of his associates most chary of self-praise, could not but feel pride in his resemblance to Silenus;note[Plato, Phaedo 215A; Xenophon, Symposium 4.19.] for his whole desire was in this - to prepare his head as receptacle of mind. But like many other of the thoughts of Socrates, this also escaped the comprehension of the dull-witted, namely that he prided himself overmuch on his likeness to Silenus. The fact that the blossom of hair well befits youths at the moment of life when we have not yet begun to reason, but flits away from age and does not await maturity which manifestly makes mind and thought to dwell with living creatures, this you must surely admit condemns the nature of hair as bereft of reason.
 "But if a man has hair even although aged?" you say. Well, some old men may also be devoid of sense, nor perchance do all men attain the perfection of manhood. The case therefore stands thus, that mind and hair do not await each other but yield place as darkness does to light. Now to those seeking the cause of this the answer is somewhat cryptic. We will attempt, however, to say what is sufficient for the present purpose, taking care to enshroud with purity all that is inviolable.