How is reductio ad absurdum used in philosophy?
Reductio ad absurdum is used in philosophy to uncover flaws and inconsistencies in various theories and beliefs.
For example, the following reductio ad absurdum argument is inspired by Emmanuel Kant:
“If moral relativism is true and all moral beliefs are equally valid, then the beliefs that ‘helping others is a moral duty’ and ‘helping others is never a moral duty’ must both be valid. This leads to a contradiction, as an action cannot be both a moral duty and not a moral duty simultaneously.”
This argument exposes how moral relativism defies the law of non-contradiction, encouraging further examination and refinement of moral theories.