shalt get kings, though thou be none:"
             Their exact meanings are never clear and even their appearances are confusing, as Banquo states:
             And yet your beards forbid me to interpret
             That you are so." Act 1 Scene 3, lines 45-47
             Characters can sometimes appear to be under the influence of the witches at crucial points in the play, such as when Lady Macbeth calls upon evil spirits, it is very similar to a spell:
             That tend on mortal thoughts! Unsex me here,
             And fill me from the crown to the toe top-full
             Of direst cruelty; make thick my blood,
             Stop up the access and passage to remorse,
             That no compunctious visitings of nature
             Shake my fell purpose, nor keep peace between
             Th'effect and it!" Act 1 Scene 5, lines 39-46
             However, by the end of the play, it is more like Macbeth has recited this incantation, as he has become cold and destroyed everything that was ever good about himself. He cannot even find it in his heart to grieve for his wife, saying simply that she should have picked a better time to die.
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