MACBETH                  If’t be so,

For Banquo’s issue have I filed my mind,

For them the gracious Duncan have I murdered,

Put rancours in the vessel of my peace

Only for them, and mine eternal jewel

Given to the common enemy of man,

To make them kings, the seeds of Banquo kings.

Rather than so, come fate into the list

And champion me to th’ utterance. (3.1.64-72)

So: if the witches’ prophecy is true, then for Banquo’s issue have I filed my mind. Filed here is defiled, polluted, corrupted—and the ear perhaps supplies fouled, too, one of the play’s key words, and suggesting the sense (all those birds) of fouling a nest, perversely destroying your own home. Filed also, of course, suggests the action of filing, and however inaccurately, that resonates here, the sense of sharpening, of something flayed, exposed, abraded. Macbeth will think about his soul in a line or two, but here it’s his mind, everything he thinks about, the very way that he thinks, irremediably altered. The voice of obsession, and although I’m usually sceptical about sound effects, the assonance of I filed my mind—I, I, I, I—is striking (!), with a primal (!!) quality; a keen, a cry. All for Banquo’s children, not his own, for he has none. I’ve murdered the gracious Duncan for them: Macbeth never attempts to justify his action by casting aspersions on Duncan, smearing his record; Duncan remains the good king. I have put rancours in the vessel of my peace, another image of pollution, a poisoned, bitter chalice, but perhaps also, if the vessel is his mind, his conscience, there’s a physical sense too of discomfort. Rancour can be connected with the verb to rankle, which more precisely suggests rottenness, a foul, festering wound; it’s got a physicality to it. I’ve done such wrong, and sustained such damage, such moral injury—for Banquo’s sons? And I have sold my soul, given mine eternal jewel to the common enemy of man, to Satan, to make them kings, the seeds of Banquo kings. I’ve damned myself, lost myself, for the sake of another man’s children. Time to do something, therefore, calling on fate to fight on my side, like a champion, or else (and perhaps more likely) I’m going to challenge fate, take on this prophecy, and prove it wrong; I’ll fight to the death.