Truth value

In logic, the truth value of a logical statement says how much it is true. Usually, the truth value can only be "true" or "false". For example, "The car is red" is true when the car is red, and false when it is not. The "true" truth value is often written as $\top$, T or 1, and the "false" truth value as $\bot$, F or 0. The truth value of a complex statement can be found using a chart called truth table.

In multi-valued logics, the truth value can be other values as well. For example, one could use a value between 0 and 1 to say how much it is true. Zero would mean that it is completely false, and one would mean that it is completely true. When the car is orange (and we define orange as half red, half yellow), the truth value could be 0.5 because the statement is half true and half false. it is also used in critical thinking.

Related pages

• Fuzzy logic, a multi-valued logic
• Tautology (logic)