In stature he was a little below the common height; his skin was foul and spotted; his hair inclined to yellow; his features were agreeable rather than handsome; his eyes grey and dull, his neck was thick, his belly prominent, his legs very slender, his constitution sound. For, though excessively luxurious in his mode of living, he had, in the course of fourteen years, only three fits of sickness; which were so slight, that he neither forbore the use of wine, nor made any alteration in his usual diet. In his dress, and the care of his person he was so careless, that he had his hair cut in rings, one above another; and when in Achaia, he let it grow long behind; and he generally appeared in public in the loose dress which he used at table, with a handkerchief about his neck, and without either a girdle or shoes.

He was instructed, when a boy, in the rudiments of almost all the liberal sciences; but his mother diverted him from the study of philosophy, as unsuited to one destined to be an emperor; and his preceptor, Seneca, discouraged him from reading the ancient orators, that he might longer secure his devotion to himself. Therefore, having a turn for poetry, he composed verses both with pleasure and ease; nor did he, as some think, publish those of other writers as his own. Several little pocketbooks and loose sheets have come into my possession, which contain some well-known verses in his own hand, and written in such a manner, that it was very evident, from the blotting and interlining, that they had not been transcribed from a copy, nor dictated by another, but were written by the composer of them.