Validity - Preservation

Preservation

In truth-preserving validity, the interpretation under which all variables are assigned a truth value of 'true' produces a truth value of 'true'.

In a false-preserving validity, the interpretation under which all variables are assigned a truth value of 'false' produces a truth value of 'false'.

Preservation properties Logical connective sentences
True and false preserving: Logical conjunction (AND, ) • Logical disjunction (OR, )
True preserving only: Tautology ( ) • Biconditional (XNOR, ) • Implication ( ) • Converse implication ( )
False preserving only: Contradiction ( ) • Exclusive disjunction (XOR, ) • Nonimplication ( ) • Converse nonimplication ( )
Non-preserving: Proposition • Negation ( ) • Alternative denial (NAND, ) • Joint denial (NOR, )

Read more about this topic:  Validity

Famous quotes containing the word preservation:

    “Is not our role to stand for the one thing which means our own salvation here but with which it will also be possible to save the world, and with which Europe will be able to save itself, namely the preservation of the white man and his state?”
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