The Shakespeare Code apparent ontological paradox by inspiring Shakespeare to borrow phrases that the Doctor quotes from his plays. Examples of this include the Doctor telling Shakespeare that "all the world's a stage" (from "As You Like It") and "the play's the thing" (from "Hamlet"), as well as the name Sycorax from "The Tempest". However, when Shakespeare himself coins the phrase "To be, or not to be", the Doctor suggests he write it down, but Shakespeare considers it "too pretentious". In a different version of the joke, the Doctor exclaims "Once more unto the breach", and Shakespeare initially likes the phrase, before realising
The Shakespeare Code "Sycorax" to Shakespeare, Shakespeare says that he will use the name (the joke is that the name in fact derives from Caliban's mother in Shakespeare's play "The Tempest".) Other sequences include subtle references to much earlier episodes. One of the putative lines of "Love's Labour's Won", "the eye should have contentment where it rests", is taken from episode three of the 1965 serial "The Crusade" — a story consciously written in Shakespearean style. The episode concerns the "lost" Shakespeare play "Love's Labour's Won", which is referred to in more than one historical document, but which may be just an alternative