Artemidorus writes a letter to Caesar In ACT II, SCENE DIII
He is trying to warn Caesar of the assassination plot.
The purpose of the conversation between Calphurnia and Caesar was to try to warn Caesar of a plot to kill him. Calphurnia as Caesar\'s wife and had dreamt of Caesar\'s murder.
Julius Caesar did not change his mind. He was due to attend the meeting of the senate. Mark Antony was warned about the assassination plot and wanted to warn him. However, he was diverted by one of the plotters and Caesar remained unaware of the plot and went ahead with his schedule.
I don't know about the reasoning in the play, but in reality Marc Antony was not included in the murder plotbecause he was totally loyal to Caesar andif he heard the slightest hint of a plot he would warn Caesar.
Artemidorous was the teacher that tried to warn Caesar. "Caesar, beware of Brutus; take heed of Cassius; come not near Casca; have an eye to Cinna, trust not Trebonius: mark well Metellus Cimber: Decius Brutus loves thee not: thou hast wronged Caius Ligarius. There is but one mind in all these men, and it is bent against Caesar. If thou beest not immortal, look about you: security gives way to conspiracy. The mighty gods defend thee! Thy lover, 'ARTEMIDORUS.' Here will I stand till Caesar pass along, And as a suitor will I give him this. My heart laments that virtue cannot live Out of the teeth of emulation. If thou read this, O Caesar, thou mayst live; If not, the Fates with traitors do contrive."
Artemidorus is important because he is trying to warn Caesar of the conspirators and that Brutus is planning against him. He writes a letter to tell him and Caesar does not accept it before going into the Senate.
give Caesar a letter to warn him about the sonspirators plan
To warn Caesar to beware of the Ides of March.
If you mean in the play Julius Caesar, I don't know. If you mean in reality, no, he didn't warn Caesar because he didn't know anything about the conspiracy.
give Caesar a letter to warn him about the sonspirators plan
I tried to warn you that those brakes were worn out.
The Soothsayer had already cautioned Caesar about the ides of March but Caesar again paid no attention to it saying that the soothsayer was a lunatic and was hindering his way. Then on that very day when Caesar said very confidently that the Ides of March are come, he replied that it wasn't yet passed. This was a clear warning to Caesar about being prepared for any worse circumstance in future. But, as pride hath a fall, the same way Caesar went on with the days activities too confident about his security thinking that no one could ever harm him. Artemidorus had written a letter of precaution for Caesar in which he had mentioned the names of all the conspirators but failed to deliver it to Caesar because he said to him to read his petition first as it concerned Caesar personally. So, Caesar refused it saying that which considers him first shall be dealt with at the last. These warnings were over looked by Caesar which paved the way for his death.