In this scene, Artemidorus reads aloud a letter that he plans to present to Caesar. The letter provides a warning to Caesar about the plot against him, and even includes the names of some of the conspirators. He warns Caesar that if he "best not immortal," to be very cautious. He acknowledges the possibility that his letter may be in vain, but says that if the conspirators are successful, "the Fates with traitors do contrive."
There is some dramatic irony in the scene, because one scene earlier, Caesar has tried to dismiss Calpurnia and his priests when they fear that something bad is about to happen. He allows himself to be persuaded by Decius Brutus, one of the men Artemidorus warns him about, to leave his house and attend the Senate.
Later, the scene provides considerable drama, as Caesar declines to read the letter from Artemidorus. He favors his pride ahead of the concern of the man urgently handing him the letter on his way to the Senate. Caesar believes his most loyal supporter to be mad, so he does not read the letter that may have saved his life. He proceeds to the Senate, where he is assassinated by the conspirators named in the letter.
This dramatic turn of events raises the question, common in Shakespeare's tragedies, whether Caesar is in fact fated to die. Shakespeare raises the question of whether his arrogance and hubris brought about his demise.