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Key Insights Into the Explosion Principle

3 min readApr 12, 2025

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Explosion!
By on .

In a world without contradiction, we could not distinguish between the consistent and the inconsistent.

The explosion principle

The principle of explosion states that from a contradiction, anything follows. In Latin: ex falso quodlibet (“from falsehood, anything is pleased”). Etymologically, quodlibet combines:

  • quod (“what” or “that which”),
  • libet (“it pleases” or “is agreeable”).

In medieval scholastic debates, a quodlibet was a type of open discussion where any question (quodlibetales quaestiones) could be posed and debated.

Over time, the term also entered music (e.g., a quodlibet as a composition combining multiple melodies) and philosophy, particularly in the phrase “from falsehood, anything [follows]”, another name for the principle of explosion.

In classical logic if one accepts both a statement and its negation, the system becomes trivial — meaning everything becomes provable, rendering logical distinctions meaningless. Imagine a acourt ruling “Defendant is guilty” and “Defendant is innocent.” Or a patient’s chart stating “patient has COVID-19” and “does not have COVID-19.”

Philosophy Today
Philosophy Today

Published in Philosophy Today

Philosophy Today is dedicated to current philosophy, logic and thought.

Pedro Barbalho
Pedro Barbalho

Written by Pedro Barbalho

Deeply interested in Science Fiction and Philosophy. [email protected] Currently seeking a literary agent.

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