This is a short but economical scene; some might say it is undramatic, but it serves a useful purpose. The brief action hinges around the use of Artemidorus’ letter to Caesar, warning him to beware of the several plotters against his life. The quizzical might wonder how Artemidorus knows of the plot, but in the theatre the action passes swiftly enough that perhaps only the fully alert will realize this point. (In fact, Artemidorus is a historical figure, and knew about the plot because he knew some of the conspirators, and doubtless Shakespeare picked this up in his source.) Additionally, dramatists of all stripes (even the redoubtable Bernard Shaw who generally deprecated the use) use letters as a means to further the action/plot (one of Shakespeare’s notable uses occurs in Romeo and Juliet, with concomitant dire consequences). Shakespeare does flesh out Artemidorus’ scene a little. After having him read his letter out loud (otherwise the audience would not know its content!!), Artemidorus provides a snippet of commentary favourable to Caesar: “My heart laments that virtue cannot live / Out of the teeth of emulation.” Moreover, he ends the scene with the suitably ominous lines: :If thou read this, O Caesar, thou mayest live; / If not, the Fates with traitors do contrive.” (NB: Fate, traitors, connivance–all aspects of murderous plots.)
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