If you think an argument is wrong, present the logic and/or evidence to support your side. Meta-discussion doesn't go very far and specifically, ad hominem arg

If you think an argument is wrong, present the logic and/or evidence to support your side. Meta-discussion doesn't go very far and specifically, ad hominem arguments like discrediting the messenger doesn't do anything to address the veracity of a story -- at least not from the perspective of rhetoric and formal logic. By way of example (and not to say that "two wrongs make a right"), an argument always used by climate-change believers (is there a better term? I don't want to say "supporters") is that they must be considered in the right because a preponderance of scientists agree with them. Yet recently, we've seen that those books were cooked, and that fewer scientists than they claimed were in agreement. Now, does the fact that we now know they were acting unethically mean that we should simply discard everything they've said? I think not; it simply means that we must apply a greater degree of skepticism.