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Logical Proposition

Table of Contents

What is a
Logical Proposition

True Value

AND and OR




Logical Formula
Calculation Order



Since the Greek Era, people have been interested in the method of obtaining the truth with "words." How can we realize the truth from words such as "that flower is red or white" and "that flower is not white" without even looking at the flower? Certainly, from the words that were previously confirmed to be true, we can derive some other truth that is reassuring without actually finding out the truth.

One can state that it is one of the functions of words. That functionality is researched in Logic.

When either true or false is the main question, it is called "proposition." New propositions can be constructed by connecting two previously defined propositions with conjunctions. "Logical Proposition" tries to acquire the truth of the new proposition when the truth of the older propositions are already determined.

True is expressed with T and false is expressed with F. AND, OR, exclusive or (XOR), imply (IMP), and equivalent (EQV) are conjunctions. Prefixing NOT only changes the value of one proposition. The above is called a "Logical Proposition."