Brutus has to be a liar, because in this game, it's impossible for anyone to say that he or she is a liar. Caesar is a liar, because if he was telling the truth, it would mean that he himself would be a liar, so therefore, he is not a truth teller, and he must be a liar. So since Caesars' statement was a lie, the opposite of what he said must be true. The opposite of what Caesar said would be; if one of us is a liar, then not all of us are liars. What that really means is that there is at least one truth teller among them. So that must mean that Augustus is a truth teller. To sum it up: Brutus- liar, Caesar- liar, Augustus- truth teller.