Conceit

    In literary terms, a conceit[1] is an extended metaphor with a complex logic that governs an entire poem or
    poetic passage. By juxtaposing images and ideas in surprising ways, a conceit invites the reader into a more
    sophisticated understanding of an object of comparison.

    Metaphysical conceit
    The term is generally associated in contemporary usage with the 17th century metaphysical poets. In the
    metaphysical conceit, metaphors have a much more purely conceptual, and thus tenuous, relationship to the
    thing being compared. Helen Gardner[2] observed that "a conceit is a comparison whose ingenuity is more
    striking than its justness" and that "a comparison becomes a conceit when we are made to concede likeness
    while being strongly conscious of unlikeness." An example of the latter would be George Herbert's "Praise (3)," in
    which the generosity of God is compared to a bottle which ("As we have boxes for the poor") will take in an
    infinite amount of the speaker's tears.

    An often-cited example of the metaphysical conceit is the metaphor from John Donne's "The Flea," in which a flea
    that bites both the speaker and his lover becomes a conceit arguing for the depth of their union:

      Oh stay! three lives in one flea spare
    Where we almost, yea more than married are.
      This flea is you and I, and this
    Our marriage-bed and marriage-temple is.
    When Sir Philip Sydney begins a sonnet with the conventional idiomatic expression "My true-love hath my heart
    and I have his", but then takes the metaphor literally and teases out a number of literal possibilities and
    extravagantly playful conceptions in the exchange of hearts, the result is a fully-formed conceit.

    History of the term
    In the Renaissance, the term (which is related to the word concept) indicated any particularly fanciful expression
    of wit, and was later used pejoratively of outlandish poetic metaphors.

    Recent literary critics have used the term to mean simply the style of extended and heightened metaphor
    common in the Renaissance and particularly in the 17th century, without any particular indication of value. Within
    this critical sense, the Princeton Encyclopedia makes a distinction between two kinds of conceits: the
    Metaphysical conceit, described above, and the Petrarchan conceit. In the latter, human experiences are
    described in terms of an outsized metaphor (a kind of metaphorical hyperbole), like the stock comparison of eyes
    to the sun, which Shakespeare makes light of in his sonnet 130: "My mistress' eyes are nothing like the sun."

    Other uses
    For later literature and film, the term is sometimes used (somewhat inaccurately) to refer to a device that
    stretches reality to take advantage of what Samuel Taylor Coleridge called the "willing suspension of disbelief."
    This usage is seldom seen in formal literary criticism.

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