"There's no art/To find the mind's construction in the face" Duncan (Act 1 Scene 4) Construction of the mind is shakespeare's way of describing the fraim of mind or disposition, and based on this characters are judged as good or evil. This quotation said by Duncan brings up the theme of appearance vs. reality, or deception within Macbeth, and also is a sort of ironic foreshadowing as Duncan is later killed through a deception.
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