What is a statement that is true and false?

A true-false statement is any sentence that is either true or false but not both. A negation of a statement has the opposite meaning of a truth value. A negations is written as ~p.

How can a statement be true and false at the same time?

Dialetheism (from Greek δι- di- ‘twice’ and ἀλήθεια alḗtheia ‘truth’) is the view that there are statements which are both true and false. More precisely, it is the belief that there can be a true statement whose negation is also true. Such statements are called “true contradictions”, dialetheia, or nondualisms.

What is a false statement in logic?

A false statement is a statement that is not true. Although the word fallacy is sometimes used as a synonym for false statement, that is not how the word is used in philosophy, mathematics, logic and most formal contexts. A false statement need not be a lie.

Why identifying true is important?

Truth is important. Believing what is not true is apt to spoil people’s plans and may even cost them their lives. Telling what is not true may result in legal and social penalties. Conversely, a dedicated pursuit of truth characterizes the good scientist, the good historian, and the good detective.

When both statements can be true?

Logical equivalence occurs when two statements have the same truth value. This means that one statement can be true in its own context, and the second statement can also be true in its own context, they just both have to have the same meaning.

Can two completely opposite statements both be true?

In logic, the law of non-contradiction (LNC) (also known as the law of contradiction, principle of non-contradiction (PNC), or the principle of contradiction) states that contradictory propositions cannot both be true in the same sense at the same time, e. g. the two propositions “p is the case” and “p is not the case” …

What is false sentence?

: a statement that is known or believed by its maker to be incorrect or untrue and is made especially with intent to deceive or mislead submitted a false statement to obtain the loan also : the federal crime of concealing a material fact, making a false statement, or using documents known to be falsified — see also …

What is a declarative sentence that expresses thought and can either be true or false but not both true and false It is also called a proposition?

A proposition is a declarative sentence that is either true (denoted either T or 1) or false (denoted either F or 0).

What is logic explain the role of predicate logic and propositional logic in knowledge representation?

Propositional logic is the logic that deals with a collection of declarative statements which have a truth value, true or false. Predicate logic is an expression consisting of variables with a specified domain. It consists of objects, relations and functions between the objects.

Is a logical statement true or false?

Any logical statement, by definition, is either true or false. As we willsee, showing that a statement is true can be slightly involved (just like in life!). However, showing a statement is

Is ‘this sentence is false’ a proposition?

“This sentence is false” can be neither true nor false and is thus not a proposition. However, is “This sentence is true” true or false (or both)? And hence, is “This sentence is true” a proposition?

Can a sentence be neither true nor false?

If so, a sentence like: “This sentence is false”, that can be neither true nor false, is not a meaningful sentence to be used in the context of propositional logic. “This sentence is true”? Is it paradoxical? I think so. Assume that the sentence is true; then its negation: “This sentence is not true” must be false.

What are the basic entities of logic?

Thus, if we want to stay in the realm of propositional logic, we can say that the basic entities are sentences, i.e. linguistic entities, that have a definite truth value. If so, a sentence like: “This sentence is false”, that can be neither true nor false, is not a meaningful sentence to be used in the context of propositional logic.