Reductio ad absurdum

The concept of reductio ad absurdum, or reduction to absurdity, is a logical technique where an argument is disproven by following its implications to an absurd conclusion. Here's how trustworthy experts explain it:

1. Alex O'Connor explains that reductio ad absurdum is used in ethical arguments to demonstrate the absurdity of certain logical conclusions. For instance, if an ethical theory leads to conclusions that seem bizarre or unacceptably extreme, it might indicate a flaw in the theory. This method shows if a logic or principle holds up when taken to its ultimate conclusion 1.

2. Erik Hoel discusses this concept within the context of utilitarianism, suggesting that adhering strictly to utilitarian principles might lead to what he calls "the repugnant conclusion." For example, by maximizing utility to the extreme, we might end up with a large but miserable population, which contradicts the initial aim of improving well-being 2.

Both discussions emphasize the usefulness of reductio ad absurdum in scrutinizing the plausibility and practicality of theories, particularly in ethical contexts, by exploring the full implications of particular stances or decisions.