Tautology
A tautology is a compound proposition that is always true no matter what truth values are assigned to its individual propositions. There is no way for a tautological statement to be interpreted as anything other than true. Any tautology is logically equivalent to \(1.\) The opposite of a tautology is a contradiction.
Here's an example of a tautology:
\(p \lor \lnot p\)
I am asleep or I am not asleep.
I am asleep or I am not asleep.
You can verify that a compound proposition is a tautology with a truth table. It must be true in every row, otherwise, it is definitely not a tautology.
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