Answer:
In Act 3, Scene 1 of Julius Caesar, Artemidorus is a Roman citizen who wants to warn Caesar of the assassination plot against him. Artemidorus has written a letter or petition that names the conspirators and outlines their plan. He plans to hand the petition to Caesar as he walks to the Capitol for the Senate meeting.
When Artemidorus sees Caesar passing by, he attempts to give him the letter and read it aloud, but he is brushed aside by Caesar's attendants. Caesar is then approached by several of the conspirators, including Cassius, Brutus, and Casca, who urge him to repeal a decision he has made. After they exit, Artemidorus again tries to give Caesar the letter, saying that it is a matter of personal importance for Caesar's own safety. He begs Caesar to read it and take action to prevent his own death.
Despite the objections of his attendants, Caesar does agree to read Artemidorus' petition, saying "What touches us ourself shall be last served" (Act 3, Scene 1, lines 10-11). In other words, Caesar is indicating that he will prioritize matters that directly concern him over other issues. He then begins to read the letter aloud, which includes a warning that he should beware of the men who are conspiring against him. However, before he can finish reading the letter, he is interrupted and the assassination plot is carried out.
So, Caesar reads Artemidorus' petition because he recognizes the urgency and seriousness of the warning contained in the letter. However, his decision to read the letter is ultimately futile, as he is not able to prevent his own death at the hands of the conspirators.