What does modus tollens involve in argumentation?

Modus tollens is a form of valid reasoning in propositional logic that specifically involves denying the consequent of a conditional statement. The structure of this argument is as follows: if we have a conditional statement "If P, then Q," and we know that Q is false, then we conclude that P must also be false. This logical structure is important in argumentation because it allows a speaker or writer to clearly demonstrate the invalidity of a claim by showing that its predicted outcome does not hold true.

For example, if the argument states that "If it is raining, then the ground is wet," and it is observed that the ground is not wet, one can logically conclude that it is not raining. This kind of reasoning strengthens arguments by providing a clear pathway for demonstrating the truth or falsehood of a claim through the logical implications of the conditions set within the argument.

The other options, while relevant to the overall practice of argumentation, do not accurately describe the specific function of modus tollens in logical reasoning. Providing additional evidence, affirming the antecedent, or supporting a conclusion involves different logical operations that do not capture the essence of modus tollens.