Caesar, being about to make his expedition into Africa against Cato and Scipio, committed to Brutus the government of Cisalpine Gaul, to the great happiness and advantage of that province. For while people in other provinces were in distress with the violence and avarice of their governors, and suffered as much oppression as if they had been slaves and captives of war, Brutus, by his easy government, actually made them amends for their calamities under former rulers, directing moreover all their gratitude for his good deeds to Caesar himself; insomuch that it was a most welcome and pleasant spectacle to Caesar, when in his return he passed through Italy, to see the cities that were under Brutus's command, and Brutus himself increasing his honour and joining agreeably in his progress.
Now several praetorships being vacant, it was all men's opinion that that of the chiefest dignity, which is called the praetorship of the city, would be conferred either upon Brutus or Cassius; and some say that, there having been some little difference upon former accounts between them, this competition set them much more at variance, though they were connected in their families, Cassius having married Junia, the sister of Brutus. Others say that the contention was raised between them by Caesar's doing, who had privately given each of them such hopes of his favour as led them on, and provoked them at last into this open competition and trial of their interest. Brutus had only the reputation of his honour and virtue to oppose to the many and gallant actions performed by Cassius against the Parthians. But Caesar, having heard each side, and deliberating about the matter among his friends, said, "Cassius has the stronger plea, but we must let Brutus be first praetor." So another praetorship was given to Cassius; the gaining of which could not so much oblige him, as he was incensed for the loss of the other. And in all other things Brutus was partaker of Caesar's power as much as he desired: for he might, if he had pleased, have been the chief of all his friends, and had authority and command beyond them all, but Cassius and the company he met with him drew him off from Caesar. Indeed, he was not yet wholly reconciled to Cassius, since that competition which was between them: but yet he gave ear to Cassius's friends, who were perpetually advising him not to be so blind as to suffer himself to be softened and won over by Caesar, but to shun the kindness and favours of a tyrant, which they intimated that Caesar showed him, not to express any honour to his merit or virtue, but to unbend his strength, and undermine his vigour of purpose.
Neither was Caesar wholly without suspicion of him, nor wanted informers that accused Brutus to him; but he feared, indeed, the high spirit and the great character and the friends that he had, but thought himself secure in his moral disposition. When it was told him that Antony and Dolabella designed some disturbance, "It is not," said he, "the fat and the long-haired men that I fear, but the pale and the lean," meaning Brutus and Cassius. And when some maligned Brutus to him, and advised him to beware of him, taking hold of his flesh with his hand, "What," he said, "do you think that Brutus will not wait out the time of this little body?" as if he thought none so fit to succeed him in his power as Brutus. And indeed it seems to be without doubt that Brutus might have been the first man in the commonwealth, if he had had patience but a little time to be second to Caesar, and would have suffered his power to decline after it was come to its highest pitch, and the fame of his great actions to die away by degrees. But Cassius, a man of a fierce disposition, and one that out of private malice, rather than love of the public, hated Caesar, not the tyrant, continually fired and stirred him up. Brutus felt the rule an oppression, but Cassius hated the ruler; and, among other reasons on which he grounded his quarrel against Caesar, the loss of his lions which he had procured when he was aedile-elect was one; for Caesar, finding these in Megara, when that city was taken by Calenus, seized them to himself. These beasts, they say, were a great calamity to the Megarians; for, when their city was just taken, they broke open the lions' dens, and pulled off their chains and let them loose that they might run upon the enemy that was entering the city; but the lions turned upon them themselves, and tore to pieces a great many unarmed persons running about, so that it was a miserable spectacle even to their enemies to behold.
And this, some say, was the chief provocation that stirred up Cassius to conspire against Caesar; but they are much in the wrong.
For Cassius had from his youth a natural hatred and rancour against the whole race of tyrants, which he showed when he was but a boy, and went to the same school with Faustus, the son of Sylla; for, on his boasting himself amongst the boys, and extolling the sovereign power of his father, Cassius rose up and struck him two or three boxes on the ear; which when the guardians and relations of Faustus designed to inquire into and to prosecute, Pompey forbade them, and, sending for both the boys together, examined the matter himself. And Cassius is then reported to have said thus, "Come, then, Faustus, dare to speak here those words that provoked me, that I may strike you again as I did before." Such was the disposition of Cassius.