Error 1: “A respected person said it, therefore it is certain.” Attribution and evidential relevance still need examination.
Error 2: “Many listeners agreed, therefore it is true.” Persuasion does not establish truth.
Error 3: “One indicator is present, so all alternatives are impossible.” Probable premises may admit contrary possibilities.
Error 4: “It is rhetoric, so every premise must be rejected.” Probability is not the same as falsity.
Each error is corrected by examining the premises, their provenance and their relation to the conclusion.