Contents

## What would be an example of the law of non-contradiction?

The law of non-contradiction is a rule of logic. It states that if something is true, then the opposite of it is false. For example, **if an animal is a cat, the same animal cannot be not a cat**. Or, stated in logic, if +p, then not -p, +p cannot be -p at the same time and in the same sense.

## Is the law of Noncontradiction true?

As common sense as you intuited, **law of noncontradiction (LNC) is considered to be necessarily true universally** (in all possible worlds) from which analytic statements follow from by most philosophers such as Aristotle who asserted the most certain of all basic logic principles is that contradictory propositions are

## How is the law of non-contradiction expressed?

Formally this is expressed as the **tautology ¬(p ∧ ¬p)**. The law is not to be confused with the law of excluded middle which states that at least one, “p is the case” or “p is not the case” holds. One reason to have this law is the principle of explosion, which states that anything follows from a contradiction.

## What is the meaning of non-contradiction?

Definition of noncontradiction

: **absence of logical contradiction** … the law of noncontradiction, which states that contradictory propositions cannot both be true at the same time and in the same sense.— Pat Zukeran.

## Why is law of non-contradiction important?

According to Aristotle, first philosophy, or metaphysics, deals with ontology and first principles, of which the principle (or law) of non-contradiction is the firmest. Aristotle says that **without the principle of non-contradiction we could not know anything that we do know**.

## What is an example of the law of contradiction?

Here are some simple examples of contradictions. 1. **I love you and I don’t love you**. 2. Butch is married to Barb but Barb is not married to Butch.

## What is the law of non-contradiction quizlet?

What is the Law of Non-contradiction? The Law of Non-contradiction is that **a statement CAN’T be both true and false at the same time and in the same sense**.

## Can anything 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 that 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 does it mean to be a law or principle of thought?

Laws of thought are **rules that apply without exception to any subject matter of thought**, etc.; sometimes they are said to be the object of logic.

## What is it called when two opposing things are true?

**Doublethink** is the act of simultaneously accepting two mutually contradictory beliefs as correct, often in distinct social contexts. from Wikipedia. Follow this answer to receive notifications.

## What happens when laws contradict each other?

Under the doctrine of preemption, which is based on the Supremacy Clause, **federal law preempts state law, even when the laws conflict**. Thus, a federal court may require a state to stop certain behavior it believes interferes with, or is in conflict with, federal law.

## Is contradiction always false?

**A contradiction is something that is always false**, regardless of it’s truth values.

## What is contradiction rule?

This is a basic rule of logic, and proof by contradiction depends upon it. Truth and falsity are mutually exclusive, so that: A statement cannot be true and false at the same time. If the statement can be proven true, then it cannot be false. If the statement can be proven false, then it cannot be true.

## Is proof by contradiction valid?

**yes, it is a valid line of logical reasoning** and therefore applicable to all sciences. I also admit that proof by contradiction is a valid line of logical reasoning and therefore applicable to all sciences.

## How do you prove a contradiction?

*And if X is an A bar. Then X is not going to be an A. But then we have a contradiction here. Because X is an A but X is also not an A. So that's one contradiction.*

## When should you use a proof by contradiction?

**Contradiction proofs are often used when there is some binary choice between possibilities:**

- 2 \sqrt{2} 2 is either rational or irrational.
- There are infinitely many primes or there are finitely many primes.

## What is the difference between a direct proof and a proof by contradiction?

In a proof by contrapositive, we actually use a direct proof to prove the contrapositive of the original implication. In a proof by contradiction, we start with the supposition that the implication is false, and use this assumption to derive a contradiction. This would prove that the implication must be true.

## Which of the following are accepted without proof?

**A postulate**, like an axiom, is a statement that is accepted without proof; however, it deals with specific subject matter (e.g., properties of geometrical figures) and thus is not so general as an axiom.