What Is a Paradox? | Definition & Examples

Paradoxes are thought-provoking statements or situations that seem self-contradictory or ironic. Some paradoxes reveal truths through seemingly irrational statements, while others expose flaws in conventional reasoning.

Examples of paradoxes can be found in everyday expressions, literature, and academic domains such as logic and philosophy.

What is a paradox?

A paradox is a self-contradictory statement or scenario that challenges conventional thinking. Paradoxes are often used as aphorisms to convey ironic truths (e.g., “You have to spend money to make money”).

In literature and rhetoric, paradoxes can be used as rhetorical devices or plot devices. Paradoxes are typically used in literature to express philosophical observations in a memorable and sometimes humorous way, but they can also be used satirically to express criticism.

Paradoxes also play an essential role in logic and other branches of philosophy, where they challenge established logical systems and point out gaps in human knowledge or understanding. Logical and philosophical paradoxes can affect other disciplines, including mathematics and science.

Logical paradox

Logical paradoxes point out contradictions in widely accepted ideas. In formal logic, paradoxes typically demonstrate how an argument or concept can seem valid but still lead to an absurd conclusion. Semantic paradoxes in logic (like the “liar paradox” below) highlight contradictions in language and meaning.

Set theory paradox

Set-theoretic paradoxes reveal contradictions in early set theory, a branch of mathematics that overlaps with formal logic. It deals with the study of sets, which are collections of objects. Paradoxes in early set theory (or “naive” set theory) revealed flaws that led to more sophisticated systems.

To understand the self-referential nature of Russell’s paradox, consider the barber paradox: A barber is defined as one who shaves all those—and only those—who do not shave themselves. If the barber shaves himself, he shouldn’t; if he doesn’t shave himself, he should.

Philosophical paradox

Beyond formal logic, other branches of philosophy also use logical paradoxes to point out incongruities in philosophical systems. These philosophical paradoxes typically emphasize metaphysical or epistemological questions rather than formal logical structures. Philosophical paradoxes indicate where further inquiry or more robust systems and definitions may be needed.

Literary paradox

Paradoxes in literature involve statements or plot points that seem self-contradictory but contain striking elements of truth or insight. A literary paradox can serve many purposes, such as conveying humor, absurdity, philosophical wisdom, or societal critique. Literary paradoxes often underscore a text’s core message.

Time paradoxes

A time paradox (or temporal paradox) describes a logical impossibility related to time travel. Well-known time paradoxes include the grandfather paradox, the bootstrap paradox, and the predestination paradox.

In the grandfather paradox, a time traveler kills their grandfather, preventing their own birth. If the time traveler were never born, how could they travel back in time and kill their grandfather?

The bootstrap paradox involves information or objects being sent back in time with no clear logical origin (e.g., a book is brought to the past, inspiring its own creation).

The predestination paradox involves actions by a time traveler that inadvertently cause the outcomes they were trying to influence or prevent (e.g., a person travels back in time to stop a fire but ends up causing it instead).

Frequently asked questions about paradoxes

What is the predestination paradox?

The predestination paradox is a time-travel concept in which an event is both a cause and an effect of itself.

One classic example of the predestination paradox is from the science fiction film 12 Monkeys. The film’s protagonist, Cole, is sent back in time to gather information about a virus that kills most of humanity. He eventually learns that his own actions in the past contributed to the outbreak of the virus, creating a self-referential loop of cause and effect. By trying to prevent the catastrophe, Cole is causing it.

Other time-travel paradoxes include the grandfather paradox and the bootstrap paradox.

More broadly, a paradox is a saying or scenario that seems logically contradictory or impossible, which upon closer examination reveals a deeper truth or coherence within a specific context or framework.

What is the purpose of a paradox?

Paradoxes can serve several purposes:

• In literature and rhetoric, paradoxes can be used as rhetorical or plot devices. They can add humor, provoke philosophical thought, or express critique through satire.
  • Example: “Most people are other people. Their thoughts are someone else’s opinions, their lives a mimicry, their passions a quotation.” (Oscar Wilde, De Profundis)

• In logic and other branches of philosophy, paradoxes highlight flaws or contradictions in currently accepted definitions and systems, demonstrating the need for further inquiry.
  • Example: If you keep removing grains of sand from a heap, at what point does it stop being a heap? (This problem is referred to as the “paradox of the heap,” or the “sorites paradox”).

• In everyday aphorisms, paradoxes are used to express philosophical insights and practical wisdom in a memorable and sometimes humorous way.
  • Example: “The more things change, the more they stay the same.”

What is an example of paradox in literature?

The plot of Joseph Heller’s Catch-22 is a classic example of literary paradox.

The central paradox is that airmen who are considered insane can request to be grounded and thus avoid flying dangerous combat missions. However, airmen who request to be grounded based on safety concerns are not actually insane, having the presence of mind to recognize the danger of their situation. Heller uses this paradox to satirize the circular logic of military bureaucracy.

Heller’s paradoxical narrative is the origin of the term “catch-22,” which describes any situation where contradictory rules or conditions prevent a solution or escape.

What is the difference between a paradox and an oxymoron?

Paradoxes and oxymorons both involve contradictions, but there is a key difference:

• A paradox is a complete statement or scenario that seems self-contradictory but reveals a thought-provoking truth upon further examination (e.g., “The only constant in life is change”).
• An oxymoron is a figure of speech consisting of a short phrase that combines contradictory terms for rhetorical effect (e.g., “alone together”).