May I respectfully suggest the community to gently ostracise any member who blatantly abuses logical fallacies either intentionally or due to ignorance. No need to do anything harsh but maybe ignoring such a member or replying by citing the logical fallacies that were abused and, if feeling generous, including an appropriate wikipedia link to educate ignorant ones.
Unfortunately, any amount of pleading or asking will not help. The only way to achieve what you asking for is by actively selecting which forum members are welcome and which are not. For example, by using forum as purgatory for invite-only sub-forum, or by actively bannig members with big number of low quality posts. Whichever way it is done it would require a lot of additional work from moderators.