While he was reading of the exploits of Alexander, he burst into tears, and said to his friends, ‘When he was of my age he had conquered Darius, but, up to now, nothing has been accomplished by me.’ 1
1 Cf. Plutarch's Life of Caesar, chap. xi. (712 F) and Perrin's note in vol. vii. of the L.C.L.; Dio Cassius, xxxvii. 52. 2: Suetonius, Divus Iulius, 7.