Why can some arguments be proven only through Conditional or Indirect Proof?

What is the examples reductio ad absurdum?

An example of reductio ad absurdum would be a an anti-Equal Rights advocate claiming that anyone in favor of an Equal Right Amendment must be in favor of killing babies. The reductio ad absurdum fallacy is similar to the straw person fallacy.

What proof type is reductio ad absurdum?

A form of the reductio ad absurdum argument, known as indirect proof or reductio ad impossibile, is one that proves a proposition by showing that its denial conjoined with other propositions previously proved or accepted leads to a contradiction.

What is the proof by reduction to absurdity?

Reductio ad absurdum is a Latin phrase which means “reduction to the absurd”. The phrase describes a kind of indirect proof. It is a proof by contradiction, and is a common form of argument. It shows that a statement is true because its denial leads to a contradiction, or a false or absurd result.

What is the reductio ad absurdum argument?


I see so that's reductio ad absurdum in a nutshell. It is reducing your opponent's argument to the absurd. By pushing the premises and conclusions to their logical limits or likewise strengthening

How do you write a proof by contradiction?

We follow these steps when using proof by contradiction:

  1. Assume your statement to be false.
  2. Proceed as you would with a direct proof.
  3. Come across a contradiction.
  4. State that because of the contradiction, it can’t be the case that the statement is false, so it must be true.


How do you prove a contradiction?

To prove something by contradiction, we assume that what we want to prove is not true, and then show that the consequences of this are not possible. That is, the consequences contradict either what we have just assumed, or something we already know to be true (or, indeed, both) – we call this a contradiction.

Why is proof by contradiction valid?

Proof by contradiction is a powerful mathematical technique: if you want to prove X, start by assuming X is false and then derive consequences. If you reach a contradiction with something you know is true, then the only possible problem can be in your initial assumption that X is false. Therefore, X must be true.

What is a statement that is accepted without proof?

axiom, in mathematics and logic, general statement accepted without proof as the basis for logically deducing other statements (theorems).

What is an example of contradiction?

A contradiction is a situation or ideas in opposition to one another. Declaring publicly that you are an environmentalist but never remembering to take out the recycling is an example of a contradiction. A “contradiction in terms” is a common phrase used to describe a statement that contains opposing ideas.

What do you call two words that contradict each other?

An oxymoron is a self-contradicting word or group of words (as in Shakespeare’s line from Romeo and Juliet, “Why, then, O brawling love! O loving hate!”). A paradox is a statement or argument that seems to be contradictory or to go against common sense, but that is yet perhaps still true—for example, “less is more.”

Whats the difference between a paradox and a contradiction?

A contradiction is something that cannot be true, because it refutes its premises. In the strictest sense, a paradox is something that can be neither be true nor false, because refuting the premises provides an equally false set of premises.