An antithesis (from the Greek ἀντίϑεσις) is a rhetorical figure consisting of a juxtaposition of opposing words or concepts, which acquire greater prominence from their proximity and mostly symmetrical arrangement. It can be obtained either by affirming one thing and denying together its opposite.
In logic, on the other hand, an antithesis is a thesis that contradicts another previously posed.
Fundamental is the reference to the context in which it is spoken: the term takes on three different meanings when it is understood in the context of rhetoric, everyday speech or philosophy.
If generically it indicates a simple contraposition of concepts, in rhetoric we find the antithesis only when in the contraposition there is correspondence of constructs between the members.
Recalling this contraposition soul/body, it is interesting to note how the antithesis has been the queen figure of sacred oratory: Christianity bases a large portion of its doctrine on the antinomy between concepts such as body/spirit, good/evil, punishment/reward.
In everyday speech, the antithesis generically indicates a general opposition, without pretensions of strict correspondence as in rhetoric: a thinker can be in antithesis with another, if he thinks in a radically different way.
In the philosophical language, finally, if initially indicated a generic opposition as in the examples of a few moments ago, from Kant onwards the antithesis becomes the proposition that contradicts the thesis. This value is the same that the antithesis assumes, moreover, in the argumentation (written or oral): a thesis is supported, an antithesis is opposed to it and conclusions are drawn in a synthesis.
Etymologically, the thesis is, deriving from the Greek verb “títhemi” (‘I put’), the position, the abstract act of placing something; consequently, the antithesis is the act of opposing something. Whether it’s rhetoric, philosophy or everyday chatter, there is always something to oppose: only now, instead of trivially telling someone to stop being a contrarian, we can tell him to cut out the antitheses.