Proposition refers to the semantics of a judgment (statement) (actually expressed concept), which is a phenomenon that can be defined and observed.
True proposition is a logical term. In mathematics, a declarative sentence expressed by language, symbol or formula that can judge its truth or falsehood is called a proposition. The truth value of a proposition can only take two values: true or false. True correspondence is correct and false correspondence is wrong. The truth value of any proposition is unique, and the proposition that the truth value is true is the true proposition.
Every proposition has an inverse proposition. As long as the title of the original proposition is replaced by the conclusion and the conclusion is replaced by the title, the inverse proposition of the original proposition can be obtained. But the original proposition is correct, and its inverse proposition is not necessarily correct.
For example, the inverse proposition of the true proposition "diagonal equality" is "equal angles are diagonal", which is a false proposition. Propositions are usually written in the form of "if" ... and then ... ". "If" is followed by the topic, and "Then" is followed by the conclusion.
Extended data
Propositional form
1. For two propositions, if the conditions and conclusions of one proposition are the conclusions and conditions of the other, then these two propositions are called reciprocal propositions, one of which is called the original proposition and the other is called the inverse proposition of the original proposition.
2. For two propositions, if the conditions and conclusions of one proposition are the negation of the conditions and conclusions of the other, then these two propositions are called mutually negative propositions, one of which is called the original proposition and the other is called the negative proposition of the original proposition.
3. For two propositions, if the condition and conclusion of one proposition are the negation of the conclusion and condition of the other proposition, then these two propositions are called mutually negative propositions, one of which is called the original proposition and the other is called the negative proposition of the original proposition.