Double negation

From MediaWiki
Revision as of 14:30, 20 October 2025 by Bfh-sts (talk | contribs) (Created page with "= Double negation = The law of double negation states that the negation of a negation returns the original proposition. == Statement == * ¬(¬p) ≡ p == Explanation == If it is not the case that ''p'' is false, then ''p'' must be true. This allows simplification of expressions with two consecutive negations. == Example == * "It is not true that it is not raining" is equivalent to "It is raining". * In Python: <code>not (not p)</code> evaluates to the same as <cod...")
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to navigation Jump to search

Double negation

The law of double negation states that the negation of a negation returns the original proposition.

Statement

  • ¬(¬p) ≡ p

Explanation

If it is not the case that p is false, then p must be true. This allows simplification of expressions with two consecutive negations.

Example

  • "It is not true that it is not raining" is equivalent to "It is raining".
  • In Python: not (not p) evaluates to the same as p.

Truth Table

p ¬p ¬(¬p)
T F T
F T F
Retrieved from "https://bsccs.stoney-wiki.com/w/index.php?title=Double_negation&oldid=39"