In ordinary discourse, any excess of information leads to a high degree of redundancy that obstructs communication. Poetic discourse operates in a completely opposite way: its informational overload enriches meaning through an ambiguity of a particular kind. Shakespeare’s work and personality thrive on poetic ambiguity, as seen not only in the authorship controversies perpetuated throughout centuries, but also in the construction of his artistic significations. This paper discusses some examples of discursive, structural and character opacities in Shakespeare’s plays, beginning with the witches’ equivocation in Macbeth and ending with Caliban’s problematic monstrosity in The Tempest. My analysis reveals that Shakespearean ambiguities are most efficient vehicles for the communication of complex, universally relevant meanings and dilemmas.