Cicero was sent off to Athens by his father to learn philosophy. While he was at Athens he wrote a letter to Tiro, a slave and later freedman of the Cicero family, in which he said that he was practising declamation in Greek with Gorgias but had to let him go, because his father, whom he did not want to offend, had told him to. Cicero Minor was then taught declamation in Greek by Cassius, and Latin with Brutus, the two leading conspirators in the assassination of Julius Caesar who, their deed complete, were in Greece trying to gain support for the war against the Second Triumvirate. Brutus praised Cicero and admired him for his noble spirit and his detestation of tyranny. During his time in Athens, Brutus gave Cicero command and used his services in a number of successful undertakings.