Now, just as, in spite of the likeness between Castor and Pollux as they are represented in sculpture and painting, there is a certain difference of shape between the boxer and the runner, so in the case of these young Romans, along with their strong resemblance to one another in bravery and self-command, as well as in liberality, eloquence, and magnanimity, in their actions and political careers great unlikenesses blossomed out, as it were, and came to light. Therefore I think it not amiss to set these forth before going further.
In the first place, then, as regards cast of features and look and bearing, Tiberius was gentle and sedate, while Caius was high-strung and vehement, so that even when haranguing the people the one stood composedly in one spot, while the other was the first Roman to walk about upon the rostra and pull his toga off his shoulder as he spoke. So Cleon the Athenian is said to have been the first of the popular orators to strip away his mantle and smite his thigh.1
In the second place, the speech of Caius was awe-inspiring and passionate to exaggeration, while that of Tiberius was more agreeable and more conducive to pity. The style also of Tiberius was pure and elaborated to a nicety, while that of Caius was persuasive and ornate. So also as regards their table and mode of life, Tiberius was simple and plain while Caius, although temperate and austere as compared with others, in contrast with his brother was ostentatious and fastidious.
Hence men like Drusus found fault with him because he bought silver dolphins at twelve hundred and fifty drachmas the pound. Again, their tempers were no less different than their speech. Tiberius was reasonable and gentle, while Caius was harsh and fiery, so that against his better judgment he was often carried away by anger as he spoke, raising his voice to a high pitch and uttering abuse and losing the thread of his discourse.
Wherefore, to guard against such digressions, he employed an intelligent servant, Licinius, who stood behind him when he was speaking, with a sounding instrument for giving the tones of the voice their pitch. Whenever this servant noticed that the voice of Caius was getting harsh and broken with anger, he would give out a soft key-note, on hearing which Caius would at once remit the vehemence of his passion and of his speech, grow gentle, and show himself easy to recall.