Final answer:
Proof and refutation procedures, when combined, sometimes generate a contradiction to test the validity of arguments. By using deductive reasoning and counterexamples, these techniques assess and refine the logical structure of arguments to discover truth.
Step-by-step explanation:
The proof and refutation procedures, when combined, serve as a decision procedure because they sometimes generate a contradiction (option c). The purpose of these procedures is to test the validity of arguments through a logical analysis. A contradiction is considered a flaw within an argument, indicating that at least one of the premises or the conclusion must be false. Whereas proof procedures aim to show that a proposition logically follows from premises, refutation techniques involve demonstrating that an argument leads to a contradiction, thus invalidating it. Counterexamples play a crucial role in refutation by providing specific instances where the argument does not hold, showing the necessity of reassessing the original premises or conclusion.
To elaborate, deductive reasoning is designed to provide certainty for conclusions based on given premises. If the premises are true, then the conclusion must be true in a valid deductive argument. However, if a counterexample can be found, this demonstrates a breakdown in the logical structure of the argument, leading to the need for refutation and further assessment. This ongoing process of proof and refutation ensures that arguments can be critically evaluated and refined, which aligns with the overarching objective of discovering truth and reliable knowledge.