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Negation (not)

Any proposition P can be converted into its negation with a negation operator, producing the new, complex, proposition:

    Not P

The proposition Not P is true if and only if P is false. It is false only if P is true. The truth table for Not P is as follows:

Examples

P

Q   Not P
T T   F
T F   F
F T   T
F F   T
Comment
It does not matter whether Q is true or false. Every time, Not P is true if P is false, and false if P is true.

About Stephen Downes

Many kudos are owed to Stephen Downes, the logician who originally authored this list of fallacies and made it freely available on the Web. His basic structure remains. A mirror of Downes' original site can be found here.