This document defines and explains various fallacies of relevance and presumption. Fallacies of relevance appeal to irrelevant factors rather than the truth or quality of evidence. These include ad hominem, tu quoque, appeal to desire, ad populum, ad baculum, ad misericordiam, ad ignorantiam, and ad verecundiam fallacies. Fallacies of presumption rely on unwarranted assumptions, such as hasty generalization, availability heuristic, confirmation bias, misleading vividness, begging the question, and slippery slope.