FALLACIES

 

A fallacy is an incorrect way of reasoning.

More narrowly, a fallacy is any attempt to persuade

emotionally or psychologically, but not logically.

 

AMBIGUITY – The fallacy of ambiguity occurs when we use a word or phrase in such a way that its meaning is not clear or can be taken in more than one way.

 

GENETIC FALLACY – A genetic fallacy is an abusive appeal that consists of attempting to discredit a position by condemning its source (genesis) or to establish a position by condemning the source of an opposed viewpoint.

 

AD HOMINEM – Ad hominem is Latin for “to the man.” The fallacy of ad hominem consists in attacking the person rather than the person’s argument.

 

INVINCIBLE IGNORANCE – Invincible ignorance is the fallacy of insisting on the legitimacy of an idea or principle despite contradictory facts.

 

QUESTIONABLE CLAIM – A questionable claim is one that cannot stand up under investigation because of the breadth of its assertion.

 

INCONSISTENCY – The fallacy of inconsistency occurs when we contradict ourselves in word or action without justification for the change of mind.

 

BEGGING THE QUESTION – Begging the question is the fallacy of answering a question with a variation of the very question asked or of assuming that the statement to be proved is true to make it look more plausible.

 

ARGUMENT FROM IGNORANCE – The argument from ignorance is the fallacy of insisting that a statement is true until proved false or false until proved true.

 

FALSE APPEAL TO AUTHORITY – Authority is an alleged expert source outside the agent on whom the agent is resting his or her claim to knowledge.

 

POPULARITY, OR DEMOCRACY – The fallacy of popularity, or democracy, is a false appeal to authority that relies on numbers alone to support its claim.

 

APPEAL TO TRADITIONAL WISDOM – Traditional wisdom is the fallacy of relying exclusively on the past to justify the present.

 

PROVINCIALISM – Provincialism is the fallacy of seeing things exclusively through the eyes of one’s own group, organization, or affiliation.

 

HASTY CONCLUSION – The fallacy of hasty conclusion occurs when we make a judgment based on insufficient evidence.

 

TWO-WRONGS-MAKE-A-RIGHT – The fallacy of two-wrongs-make-a-right is the fallacy of defending what is considered wrongdoing by pointing to an instance of similar behavior.

 

STRAW MAN – The straw man fallacy consists of presenting a position in an altered version that is easier to attack than the original.

 

IS/OUGHT – The fallacy of is/ought consists of assuming that because something is the case, it ought to or should be the case; or that because something is not the case, it ought or should not be the case.

 

FALLACIES OF FAULTY CAUSATION – A causal statement asserts a relationship between two things such that one is said to bring about the other.

 

CAUSE AS A NECESSARY CONDITION – Case sometimes carries the meaning of “necessary condition” – that is, a condition that must be present if the effect is to occur.

 

CAUSE AS A SUFFICIENT CONDITION – Cause sometimes carries the meaning of “sufficient condition” – that is, a condition in whose presence the effect will always occur.

 

CAUSE AS A CONTRIBUTORY CONDITION – Cause sometimes carries the meaning of “contributory condition” – that is, a condition that helps create the total set of conditions, necessary or sufficient, for an effect.

 

CAUSAL OVERSIMPLIFICATION – Assuming that a necessary or contributory cause for an event is the sufficient cause is causal oversimplification.

 

NEGLECT OF A COMMON CAUSE – This fallacy results from failing to recognize that two seemingly related events may be not causally related at all but rather are effects of a common cause.

 

POST HOC – Asserting that one event is the cause of another merely because the first preceded the second is the post hoc (Latin for “after this”) fallacy.

 

SLIPPERY SLOPE – The slippery-slope fallacy consists in objecting to a particular action because it supposedly will lead inevitably to a similar but less desirable action, which in turn will lead to an even less desirable action, and so on down the “slippery slope” to some ultimate horror.

 

CAUSAL INFERENCE FROM STATISTICAL CORRELATION – This is the fallacy of assuming that because two phenomena as related statistically, they must be related causally.