I think that Iago carrying buckets of filth holds a few levels of importance. In terms of the dramatic purposes, it reflects how Iago still wishes to conspire and create havoc between the characters. In Shakespeare's original drama, his target is Othello. In Constance's revisionism, his target is Desdemona. In both cases, the buckets of filth he carries is representative of his malevolence. Regardless of individual, Iago's constant nature of brutal destruction through deception seems to be universal. In a more symbolic manner, the buckets of filth might represent the propensity for tragedy. One of the overriding themes in Macdonald's work is how individuals who fail to acknowledge the complexity and intricacy of human relationships are doomed to tragedy. Part of this sense of strength and resolve is embodied in Constance herself, who must go back to the Shakespearean dramas and convince women like Desdemona and Juliet not to succumb to the tragic standards that male writers bring to their female subjects. In the "buckets of filth," one sees a potential symbol to highlight how the predisposition for tragedy is not realistic and holds a tendency for personal destruction. Another symbolic significance of the buckets of filth might be the sexism that women have to endure both in the real world and in the dramatic one. The "buckets of filth" that Desdemona has to endure both exists in the tragedy and in the academic world where she is seen as a silent victim. In Iago's carrying this, one sees a symbol of sexism that women like Constance and Desdemona share in having to address and battle through in order to find their own "Wise Fool."
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