Then, overtaking his cohorts at the river Rubicon, which was the boundary of his province, he paused for a while, and realising what a step he was taking, he turned to those about him and said: “Even yet we may draw back; but once cross yon little bridge, and the whole issue is with the sword.”
As he stood in doubt, this sign was given him. On a sudden there appeared hard by a being of wondrous stature and beauty, who sat and played upon a reed; and when not only the shepherds flocked to hear him, but many of the soldiers left their posts, and among them some of the trumpeters, the apparition snatched a trumpet from one of them, rushed to the river, and sounding the war-note with mighty blast, strode to the opposite bank. Then Caesar cried: “Take we the course which the signs of the gods and the false dealing of our foes point out. The die is cast,” said he.*
* Suetonius’s account has furnished the English language with two useful sayings. ‘The die is cast’ means that a matter is now under the control of a higher power, as when a gambler who has thrown his dice must wait patiently for Fortune to favour him — or not. Similarly, to ‘cross the Rubicon’ means to pass the point of no return, to begin a course of action which, once begun, must be followed through to the end.