Caelius escaped the fate of Catiline and his crew only to fall into the hands of another clique not less dangerous for his moral welfare.  He became one of a group of brilliant young men, among whom were probably Catullus and Calvus the poets, who were lovers, and passionate lovers, of the infamous Clodia; they were needy, she found them money, and they hovered about her like moths about a candle.  In such a life of passion and pleasure quarrels were inevitable.  If the Lesbia of Catullus be Clodia, as we may believe, she had thrown the poet over with a light heart.  It was apparently of his own free will that Caelius deserted her:  in revenge she turned upon him with an accusation of theft and attempt to poison.  What truth there was in the charges we do not really know, but Cicero defended him successfully, and in this way we come to know the details of this unsteady life.

In gratitude, and possibly in shame, Caelius now returned to his old friend, and abandoned the whole ring of his vicious companions for diligent practice in the courts, where he obtained considerable fame as an orator.  A fragment of a speech of his preserved by Quintilian shows, as Professor Tyrrell observes, wonderful power of graphic and picturesque utterance.[194] Cicero, writing of him after his death,[195] says that he was at this time on the right side in politics, and that as tribune of the plebs in 56 he successfully supported the good cause, and checked revolutionary and seditious movements.  All was going well with him until Cicero went as governor to Cilicia in 51.  Cicero seems to have felt complete confidence in him, and invited him to become his confidential political correspondent; fifteen out of his seventeen letters were written in this capacity.  These letters show us the man as clearly as if we had his diary before us.  Caelius is no idle scamp or lazy Epicurean; his mind is constantly active:  nothing escapes his notice:  the minutest and most sordid things delight him.  He is bright, happy, witty, frivolous, and doubtless lovable.  It is amusing to see how Cicero himself now and again catches the infection, and tries (in vain) to write in the same frivolous manner.[196] Caelius has some political insight; he sees civil war approaching, but he takes it all as a game, and on the eve of events which were to shake the world he trifles with the symptoms as though they were the silliest gossip of the capital.[197] In none of these letters is there the smallest vestige of principle to be found.  On the very eve of civil war he tells Cicero[198] that as soon as war breaks out the right thing to do is to join the stronger side.  Judging Caesar’s side to be the stronger, he joined it accordingly, and did his best to induce Cicero to do the same.  As M. Boissier happily says, he never cared to “menager ses transitions.”