Definition: A declarative sentence (statement) that can judge whether it is true or not is called a proposition. Note: A statement that is not a declarative sentence is not a proposition. For example, "Is 2 bigger than 3?" For a proposition, the statement is either true or false, and it is impossible to be true and false at the same time. The correct proposition is called true proposition, and the wrong proposition is called false proposition.

# proposition # true proposition # false proposition