Quantification fallacies
A quantification fallacy is an error in logic where the quantifiers of the premises are in contradiction to the quantifier of the conclusion.
Types of quantification fallacies:
Existential fallacy β an argument that has a universal premise and a particular conclusion.[11]
Formal syllogistic fallacies
Syllogistic fallacies β logical fallacies that occur in syllogisms.
Affirmative conclusion from a negative premise (illicit negative) β a categorical syllogism has a positive conclusion, but at least one negative premise.[11]
Fallacy of exclusive premises β a categorical syllogism that is invalid because both of its premises are negative.[11]
Fallacy of four terms (quaternio terminorum) β a categorical syllogism that has four terms.[12]
Illicit major β a categorical syllogism that is invalid because its major term is not distributed in the major premise but distributed in the conclusion.[11]
Illicit minor β a categorical syllogism that is invalid because its minor term is not distributed in the minor premise but distributed in the conclusion.[11]
Negative conclusion from affirmative premises (illicit affirmative) β a categorical syllogism has a negative conclusion but affirmative premises.[11]
Fallacy of the undistributed middle β the middle term in a categorical syllogism is not distributed.[13]
Modal fallacy β confusing necessity with sufficiency. A condition X is necessary for Y if X is required for even the possibility of Y. X does not bring about Y by itself, but if there is no X, there will be no Y. For example, oxygen is necessary for fire. But one cannot assume that everywhere there is oxygen, there is fire. A condition X is sufficient for Y if X, by itself, is enough to bring about Y. For example, riding the bus is a sufficient mode of transportation to get to work. But there are other modes of transportation β car, taxi, bicycle, walking β that can be used.
Modal scope fallacy β a degree of unwarranted necessity is placed in the conclusion. (lb)