Antithesis (plural: antitheses; from Greek, meaning "setting opposite") is a technique used in writing or speech. It can either present a statement that contrasts with or goes against a previous statement, or it can introduce two opposite ideas together to highlight their differences.

Antithesis is a figure of speech that uses apparent opposite ideas, words, phrases, or sentences. These opposites are arranged in a balanced structure, often using similar patterns in the sentence to emphasize the contrast between the ideas.

An antithesis always includes two ideas in one statement. These ideas may not look opposite in structure, but they act as opposites when compared to show differences clearly.

According to Aristotle, using antithesis helps an audience understand a speaker’s message better. Comparing two ideas or situations makes it easier to decide which one is better. Aristotle also said that antithesis in speeches is similar to syllogism, a type of logical reasoning that presents two statements to reach a conclusion.

Antitheses are used to make arguments stronger by showing exact opposites or simply different ideas. They can include both. These contrasts often make sentences easier to remember because of the balance and emphasis given to the words.

Rhetorical antithesis

Antithesis is a rhetorical device that uses clear contrasts in words or sentences to highlight differences in ideas. The structure of these contrasts is usually parallel.

The term "antithesis" has been used since the 4th century BC. For example, Aristotle discussed it in his work Rhetoric around 1410a, where he provided several examples.

An antithesis can be a simple statement that contrasts two things using a parallel structure:
• "I defended the Republic as a young man; I will not leave it now that I am old." (Cicero, 2nd Philippic, 2.118)

Sometimes, two contrasts appear together. In the proverb "Man proposes, God disposes," the word "man" is contrasted with "God," and "proposes" is contrasted with "disposes."

Another type uses a "not A, but B" structure (negative-positive), emphasizing a point by first contrasting it with its opposite:
• "I came not to bring peace but a sword." (St Matthew's Gospel, 10:34)

Another type involves reversing the order of words (antimetabole):
• "In peace you long for war, and in war you long for peace."
• "Two things show feebleness of mind: holding your breath at the time for speaking, and speaking when you should be silent." (Saadi)

Negative-positive antithesis and antimetabole can be used together, as in:
• "Ask not what your country can do for you—ask what you can do for your country." (Inauguration of John F. Kennedy, 1961)

Antithesis can also be combined with synonymous parallelism. In one example, the first and second parts of a couplet use the same adverb and verb, while contrasting "evil" with "right" and "filthy" with "holy."

Kenneth Burke, a 20th-century rhetorician, wrote about how antithesis affects how people feel and think in his book A Rhetoric of Motives, one of his most famous works.

Other examples of antithesis include:
• "Give every man thy ear, but few thy voice." (William Shakespeare, Hamlet)
• "For many are called, but few are chosen." (Matthew 22:14)
• "Never give in—never, never, never, never, in nothing great or small, large or petty, never give in except to convictions of honor and good sense." (Winston Churchill)
• "It was the best of times, it was the worst of times, it was the age of wisdom, it was the age of foolishness…" (Charles Dickens, A Tale of Two Cities)
• "We must learn to live together as brothers or perish together as fools." (Martin Luther King Jr., speech at St. Louis, 1964)
• "The world will little note, nor long remember what we say here, but it can never forget what they did here." (Abraham Lincoln, The Gettysburg Address, 1863)
• "He who desires peace, should prepare for war." (Vegetius, Epitoma Rei Militaris, book 3, introduction)
• "For now we see in a mirror dimly, but then face to face. Now I know in part; then I shall understand fully…" (St Paul, 1st Epistle to the Corinthians 13:12, Revised Standard Version-Catholic Edition)
• "My men have become women, and my women, men." (King Xerxes at the Battle of Salamis (480 BC), according to Herodotus 8.88.3)
• "Senator, in everything I said about Iraq I turned out to be right and you turned out to be wrong." (George Galloway at a US Senate hearing, May 2005)
• "I'm not saying that this or that statue was stolen from there; I'm saying this, that you, Verres, left not one single statue in Aspendus." (Cicero, In Verrem, 2.1.53)
• "I have a dream that my four little children will one day live in a nation where they will not be judged by the color of their skin but by the content of their character." (Martin Luther King Jr., 1963)
• "For contemplation he and valour formed, for softness she and sweet attractive grace; he for God only, she for God in him." (John Milton, Paradise Lost)

The "Antitheses" in St Matthew's Gospel

Matthew's Antitheses is the common name for a part of the Sermon on the Mount where Jesus explains six well-known rules from the Mosaic Law and tells his followers to do more than the Law says. Since the Reformation, Protestant scholars have generally believed that Jesus was offering his teachings as a contrast to incorrect ways people were interpreting the Law at that time. The word "antithesis" was used by Marcion of Sinope to describe a statement in which he compared the Old Testament with the New Testament, leading to the creation of a belief called Marcionism.

In philosophical discussion

In dialectics, which is a method of reasoning that finds truth through the exchange of logical arguments, antithesis refers to the placement of opposing ideas next to each other, often in a fair and even way. These arguments are typically presented in the order of thesis, antithesis, and synthesis.

This style of philosophical discussion—introducing an idea, then its opposite, and finally reaching a conclusion—was used by ancient philosophers. However, the specific use of the terms "thesis, antithesis, synthesis" to describe this process began in the 18th century. It was first introduced in a book published in 1794 by the German philosopher Johann Gottlieb Fichte.

Some people mistakenly believe the phrase originated with the German philosopher Hegel. However, Hegel only used the trio of terms once, in a lecture where he criticized Immanuel Kant for frequently using the terms "thesis, antithesis, synthesis."