An objective correlative is a literary term referring to a symbolic article used to provide explicit, rather than implicit, access to traditionally inexplicable concepts such as emotion or color.
The theory of the objective correlative as it relates to literature was largely developed through the writings of the poet and literary critic T.S. Eliot, who is associated with the literary group called the New Critics. Helping define the objective correlative, Eliot's essay "Hamlet and His Problems", republished in his book The Sacred Wood: Essays on Poetry and Criticism discusses his view of Shakespeare's incomplete development of Hamlet's emotions in the play Hamlet. Eliot uses Lady Macbeth's state of mind as an example of the successful objective correlative : "The artistic 'inevitability' lies in this complete adequacy of the external to the emotion…." , as a contrast to Hamlet. According to Eliot, the feelings of Hamlet are not sufficiently supported by the story and the other characters surrounding him. The objective correlative's purpose is to express the character's emotions by showing rather than describing feelings as discussed earlier by Plato and referred to by Peter Barry in his book Beginning Theory: An Introduction to Literary and Cultural Theory as "...perhaps little more than the ancient distinction (first made by Plato) between mimesis and diegesis…." (28). According to Formalist critics, this action of creating an emotion through external factors and evidence linked together and thus forming an objective correlative should produce an author's detachment from the depicted character and unite the emotion of the literary work. The "occasion" of E. Montale is a further form of correlative.
Although popularized by Eliot in his essay "Hamlet and His Problems" in The Sacred Wood (1921), the term was first used by the German Philosopher Arthur Schopenhauer in his 1813 treatise, On the Fourfold Root of the Principle of Sufficient Reason: "Matter is therefore only the objective correlative of the pure understanding".
In "Hamlet and His Problems", Eliot used the term exclusively to refer to his claimed artistic mechanism whereby emotion is evoked in the audience: