FALLACY TYPES

This promises to be a short posting.  It is the last entry regarding logical argument.  The last posting reviewed sources of faulty argumentation which relate to rhetoric.  This was introduced by describing three sources of misleading rhetoric often intentionally employed to convince an audience of a point, but which falls short of logical argument.  The three are ethos (based on good reputation), pathos (based on good feelings), and logos (based on insufficient evidence).  These three sources lead to recurring forms or types of fallacies.

          They are so common that logicians have been able to classify them and this posting reports on twelve types of fallacies.  They are:  appeal to ignorance, appeal to authority, appeal to popular opinion, association fallacy, attacking the person, begging the question, circular argument, false causation fallacy, false dilemma/dichotomy, illogical conclusion, slippery slope, and syllogism fallacy.

          Each can be defined and illustrated as follows:

·        Appeal to ignorance – Since the listener cannot prove something does not exist, it is therefore true.  Example:  Since one cannot “see” whether organic life exists on the side of the moon facing away from the earth, there is organic life on that side of the moon.

·        Appeal to authority – Also known as “argumentum verecundia” (argument from modesty); if someone of respect for their knowledge believes/believed in some conclusion, it must be true.  Since the genius, Einstein, rejected the unpredictability of quantum mechanics, it must not be true.

·        Appeal to public opinion – Since something is generally believed by the public, it must be true.  Example:  Since football (American style) is so popular, it should not be regulated in terms of its alleged effect on brain damage.

·        Association fallacy – Also known as “guilt by affiliation;” something is wrong, untrue, or immoral because an unsavory person believes or ascribes to it.  Example:  Since our political adversaries want this law, it must be awful and we would be wise to reject it.  Or, since my political opponent is backed by the leader of the opposition, voters should reject him/her.

·        Attacking the person – Also known as “ad hominem;” it is backing a position by insulting the person or group espousing it.  Example:  Why would anyone listen to a proposition offered by that jerk?

·        Begging the question – Posing a conclusion that is contained in the inquiry such as an attempt to sell it by restating it in other words.  Example – Since taking a day off every so often is healthy, it must be good for a person to take a vacation once a year.

·        Circular argument – Also known as “circulus in probando;” argument that uses an element of the argument to back up its conclusion instead of going outside the argument for such backing.  Example:  Since rainy days are soothing, the sight of rain mellows one’s day.

·        False causation fallacy – Also known as “cum hoc ergo propter hoc;” stating something is the cause of something else only because it proceeded the second event.  Often considered a superstition.  Example:  Every time I wear pink shoe laces, the Tigers win.  Or, they moved to Baltimore and, six months later, they are getting a divorce.  Baltimore ruined their marriage.

·        False dilemma/dichotomy – Also known as “bifurcation;” narrowing an argument to only two false options.  Example:  If you don’t accept this proposal, you must be actively seeking the bankruptcy of this business.

·        Illogical conclusion – Making a conclusion that simply does not logically follow from the evidence offered or previously established conclusions.  All loyal Americans believe in democracy, and Jane is not an American, therefore, Jane does not believe in democracy.

·        Slippery slope – If one allows an event to happen, it will lead to more serious and detrimental events to happen.  Example:  If a few illegal immigrants commits a serious crime, then being lenient on illegal immigration will lead to uncontrollable crime rates.

·        Syllogism fallacy – A conclusion derived from a syllogistically formed argument that is illogical.  Example:  All homing pigeons are white, the bird in my cage is white, therefore, it is a homing pigeon.

These forms of fallacy are common in our political discourse.  They usually are subtler than the examples offered above; that is, they sound more persuasive.  One should remember that illogical arguments can be true, it is just that the argument as presented does not make the case that it is. 

And one can guess that if a logical argument is available to a reasonably intelligent advocate, the fact that it was not used, perhaps he/she is attempting to employ illogical rhetoric to convince without having logical reasons to promote the position being argued.  If national politicians trying to appeal to anti-immigrant sentiment, cite some examples of illegal actions by a few immigrants to argue they are responsible for heightened crime rates, one is tempted to question the motivation of such argumentation.

These concerns are so central to the instructional approach this blog is promoting that a teacher would be well-served to begin each lesson with an example of an illogical argument – using one of the types just reviewed – and hold a quick contest as to which student can first identify the type it is.  Perhaps, that student can earn some extra credit.  If done at the beginning of each lesson, students in the class can get a significant amount of practice in detecting illogical arguments.