<P> In 1869, author Allan Park Paton advanced the argument that Macbeth personally served as the Third Murderer . Paton argued the successful killings of Banquo and Fleance were personally important to Macbeth, and that while the banquet that night was scheduled to start at 7 pm, Macbeth did not appear until midnight . Paton believes the Third Murderer extinguished a light to avoid recognition, and later, Macbeth tells Banquo's ghost that "In yon black struggle you could never know me ." </P> <P> Paton's theories attracted attention, with Erato Hills of the University of Cambridge calling it "very ingenious," but not supported by the play . Hills interpreted the play as portraying Macbeth, Lady Macbeth and all guests as arriving at the banquet at the same time, rather than Macbeth being late, and the mention of 7 p.m. can be attributed to Shakespeare's lack of attention to detail . Hills also believed the First Murderer was the one who extinguished the light . John Addis complimented Paton for the "quite original suggestion," citing the belief Macbeth sent the Third Murderer out of "superabundant caution," and acknowledging Macbeth could have sent himself out of that caution . Addis instead connected the Third Murderer to the spy mentioned by Macbeth in 3.1 . Scholar Henry Norman Hudson also addressed and attempted to refute speculation that Macbeth was the Third Murderer . </P> <P> The scene in which the First Murderer describes the killing of Banquo to Macbeth has been used for and against arguments of Macbeth's identity as the Third Murderer . Macbeth appears surprised Fleance has escaped, though the surprise may be feigned . </P> <P> Suggestions that the Third Murderer was the Thane of Ross were dismissed by Bertha D. Vives in 1933 for lack of evidence . Another proposed solution is that the character is a non-human personification of a concept such as Destiny . </P>

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