Julius Caesar William Shakespeare wrote the play, “Julius Caesar” with a large focus on theme in mind. He focused a great deal on deception and manipulation as one of these themes. In “Julius Caesar” Cassius manipulates Brutus into agreeing to be in the conspiracy, Decius manipulates Caesar into going to the capitol, and Mark Antony manipulates the minds of the plebeians. Cassius plays with Brutus’ mind to convince him that it would do Rome good to rid it of Caesar. Cassius accuses Brutus of being blind to the Romans’ pleas. He said the Romans were angry at Caesar and they wanted Brutus to rule. To help play on this, Cassius delivers fake letters to Brutus’ house.