Table of Contents

Fallacy #1 Potential Triggers For Incorrect Reasoning
Fallacy #2 How Many Fallacy Variants Are There?
Fallacy #3 In Philosophy, What Is An Argument?
Fallacy #4 And What Is Rhetoric?
Fallacy #5 The 12 Most Common Logical Fallacies
Fallacy #6 The Ad Hominem
Fallacy #7 Poisoning The Well
Fallacy #8 Formal and Informal Fallacies
Fallacy #9 Common Inductive Fallacies
F #10 Taxonomy of Fallacies
F #11 External Resource #1
F #12 External Resource #2
F #13 References / Bibliography
This blog post is PART-2 of a 3-Part set. To access the other two parts, click on Collections in the Top Menu then select "CO2 + Radionuclides" from the drop-down list.

Potential Triggers For Incorrect Reasoning

Note: this short list does contain some overlaps and redundancy

  • Trying to reason when under excessive physical and/or emotional stress;
  • Poor health and/or the mind being influenced by pharmaceuticals (drugs);
  • Too much watching of television / reading of MSM newspapers;
  • Your emotions are being manipulated by authority figures;
  • Being overly influenced by externally imposed (politically motivated) biases;
  • Processing wrong information — wrong data fed to you in bad faith;
  • Lack of confidence in one’s own innate ability to think critically;
  • A lack of prior exposure to this crucial field of philosophical study;
  • Presence (transient or chronic) of negative and/or destructive emotions;
  • Cognitive dissonance — whereupon the human mind requires more quiet-time to process/digest new information that is clashing with the old.

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How Many Fallacy Variants Are There?

Count The SheepThere are many more fallacy variants than are typically used in day-to-day discourse. Let us first explore some important ones in this brief yet representative list, courtesy of the WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.

Because of their close association with litigation, these four are presented by their Latin designators:

  • Hysteron proteron » the logical fallacy of using as a true premise [a statement assumed to be true] a proposition [a true or false statement that affirms or denies something] that is yet to be proved;
  • Ignoratio elenchi » the logical fallacy of supposing that an argument proving an irrelevant point has proved the point at issue;
  • Petitio, petitio principii » the logical fallacy of assuming the conclusion in the premises; begging the question;
  • Post hoc, post hoc ergo propter hoc » the logical fallacy of believing that temporal succession [a time sequence] implies a causal relation.

Inevitably, some logical fallacies are more common than others. Thus we can expect a correlation between simplicity and frequency of occurrence.

If the structure and operation of a particular fallacy is readily understood by political deviants, then we should expect its deployment by propagandists and those trained in public perception management: such as the more senior members of our ubiquitous, and global, mass media octopus.

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In Philosophy, What Is An Argument?

Two young men arguingAn argument is a fact or an assertion offered as evidence that something must be true. Normally, the singular is insufficient so an argument can also be defined as a series of statements typically used to persuade someone of something, or to present reasons for accepting a certain conclusion.

An argument should consist of a coherent set of reasons that present or support a particular point of view (POV). In other words, an argument comprises a series of reasons offered for or against the matter under discussion, which has the aim to convince or persuade the listener.

The reasons offered within the argument are called “premises”, and the proposition that the premises are offered for is called the “conclusion”.

Critical thinking—i.e., your ability to think critically and independently—is predicated upon the (your) ability to identify, reconstruct, and evaluate arguments presented to you by those engaged in rhetoric.

The appeal to rational persuasion is necessary to distinguish arguments from other forms of persuasion, such as violent threats, financial coercion, and emotional blackmail.

Be aware that during the 20th century (e.g., Edward Bernays, Propaganda, 1928) the field of argumentation grew to be very large. Today argumentation sustains an interdisciplinary field that includes rhetoric, informal logic, psychology, and cognitive science.

levels of argumentation

Sadly, it has since become the favourite tool of all western governments, as warned by George Orwell (Eric Arthur Blair). Now you know why so many graduates with ‘useless’ psychology degrees have long been “conveyor-belted” out of most western universities, in apparent preference to engineers and mathematicians, etc.

So how do we build a cogent argument? The philosophy faculty at Mercyhurst University (see the link in References/Bibliography) offers this succinct advisory, which I have slightly edited and reformatted to improve clarity.

An argument is cogent when:

It is deductively sound (true premises + true conclusion + valid inference);

It is inductively strong (valid inductive inference).

It is very difficult to obtain a sound argument about the practical affairs of the world because the major premises are often value claims and the minor premises can be challenged.

Therefore it is preferable for an argument to have at least a valid inference with justified—if the premises are not known for certain to be true—and relevant premises.

That is: an argument should have a valid inference with justified and relevant premises.

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And What Is Rhetoric?

Plato on RhetoricRhetoric is the study of effective speaking and writing. It is the art of persuasion. Through rhetoric, certain types of people attempt to inform, persuade, or motivate particular audiences in specific situations.

Because modern politics have been reshaped (corrupted) by the relativistic creed and “corporate donations gone wild”, rhetoric has since taken on highly negative connotations. Today, many if not most are apt to associate rhetoric with exaggerated or inflated talk.

“Spin-Doctoring” is a particularly corrosive and manipulative form of applied rhetoric which appears to have raised itself into a fixture in this ‘modern’ and contemporary world: one that several academics and philosophers warned, as long ago as the 1970s and early 1980s, was being rapidly feminized. By which I believe they meant we were rapidly having our culture re-jigged such that the subjective would henceforth regularly triumph over the objective.

While rhetoric does indeed refer to the art of persuasion through “carefully crafted words”, honest and well-intentioned people can still nobly engage in rhetoric! Perhaps our world would be greatly improved if more made the attempt?

Rhetological Fallacies

Rhetoric is mostly closely associated with verbal discourse, but it applies equally to the written word. Indeed the Merriam-Webster® dictionary emphasizes this when it affirms: rhetoric is the art or skill of speaking or writing formally and effectively especially as a way to persuade or influence people.

I do not believe (Twitter) Tweets qualify as rhetoric. But it is also true, I am of a “certain age” that allows me to remember taking technical exams using only a slide rule; where the concurrent or replacement use of early pocket calculators was strictly prohibited. What those brought up with a Smartphone in-hand believe will very likely be quite different. A Tweet may be something they see as profound literature! To find out perhaps we need some surveys conducted? 🙂

A scholarly definition for rhetoric can be found at the Edu*Rhetor blog. It appears inactive, but its archive still looks interesting. There you will find this short gem: Rhetoric is the study and practice of communication that persuades, informs, inspires, or entertains target audiences in order to change or reinforce beliefs, values, habits or actions.

Modes of Persuasion

Rhetoric’s basic premise is that one cannot truly separate the means from the meaning. That is to say, how one says something can convey just as much meaning as what one says.

Conversely whenever rhetoric is to be studied and scrutinized, then it must first be separated into its component parts: (a) its reputation cache (called ethos), (b) its emotional impact (called pathos), and (c) its propositional content (called logos).

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The 12 Most Common Logical Fallacies

When the average person speaks of logical fallacies they will likely have in mind most of the common-o-garden types listed here. The total count—encapsulate by all those taxonomies meticulously researched and catalogued by philosophers with Doctoral degrees—is of course much higher.

The 12 characterizations that follow have been compiled, in ad hoc fashion, from several different resources [see Bibliography]. Direct copies have been avoided by the use of my own paraphrasing:

1. Straw Man » Here, a false or made-up scenario is created in order that it may then be attacked. The technique involves painting your opponent with false colors to deflect the proper purpose of the argument. It is where one side of the argument is depicted as being so extreme no one would agree with it. This can be achieved by referring to the exception (rather than the rule) before inferring that that exception is actually the rule;

2. False Analogy [aka: Slippery Slope] » In this fallacy an argument will suggest one change (usually unwelcome) is bound to lead to another. Because we now live in a complex and interconnected world, this fallacy might actually be one of the more common of the bunch. Yet analogies do have a tendency to breakdown under scrutiny. They are inherently fragile and thus offer a thin basis for firm action based on any conclusions reached;

3. Argument from Authority »  This has been used to ‘good’ effect for many centuries, both by the Vatican, and by Judaism’s Senior Rabbis. Here we are told that Divine authority (often taken from the pages of a very old book of questionable provenance) can rightfully dictate truth. With this fallacy the words of an “expert” is used as the sole basis for the argument. Put another way, this is the 1950s “White Coat” syndrome writ large. Holding a senior position or having a PhD does not bestow infallibility on the holder. Unless and until logical reasoning (and evidence) is seen to have been properly applied and presented, then the perceived ‘authority’ of an expert should be seen as little more than opinion. Even the Gods have to sh*t;

4. Correlation equals Causation » To assume correlation implies cause is highly invalid. Does simply listening to classical music really increase intelligence? Does being ‘Jewish’ really bestow super intelligence (as many have claimed) on those who happen to adhere to the Torah and Talmud? Consider all other factors and you will soon conclude these two example propositions must be bogus. Also, one should never assume that because two things happened nearly simultaneously, one must have caused the other;

5. Psychologist’s fallacy » This is where we assume we are an unbiased audience. For example, citing our personal reading of some religious or historical text as the objective reading, and everyone else’s (of the same text) as “mere opinion”;

6. False Dilemma / False Dichotomy / Fallacy Of The Excluded Middle » Giving two extremes as the only viable alternatives to a position, when in reality there are multiple positions available. For example: “you either like it or you don’t!” Or President Bush Jnr’s claim: you’re either with us or against us! Many times, a continuum occurs between the obvious extremes that people wantonly fail to see. The universe tends to contain many “maybes” or grey/gray areas;

7. Moral Equivalence » Arguing that one complex moral event is essentially identical to some other. Implying that two moral issues carry the same weight or are otherwise similar. For example, equating being a “wage slave” with actual slavery, or being accused of ‘racism’ after justifiably criticizing the overweening conceit of your average Indian (Hindu) male;

8. Meaningless Question » If everything proved possible, then ergo the possibility must exist for the impossible: a stark contradiction, which is illogical. Consider these banal questions: “How high is up?” and “Is everything possible?” Note that “Up” only describes a direction and is therefore not a measurable. While everything may not prove possible, there may occur an infinite number of possibilities as well as an infinite number of impossibilities. Meaningless questions typically employ these empty words: “is,” “are,” “were,” “was,” “am,” “be,” or “been”;

9. Appeal To Consequences » An argument that concludes a premise (usually a belief) as either true or false based only on whether the premise leads to desirable or undesirable consequences;

10. Red Herring » Continually changing or redefining the argument, rather than following the original to its conclusion. In other words, the tactic of changing the subject in mid-debate; of arguing about a tangential topic rather than the real or original issue;

11. Begging The Question [aka: Circular Argument] » Assuming your premises, rather than explaining them. “Killing animals is wrong because it’s nothing less than cruelty!” or “Banning immigration would be wrong because that’s racist!” These are not arguments – they instead beg the question;

12. Appeal To Ignorance [aka: Non-Testable Hypothesis] » This fallacy asserts a proposition is true because it has not yet been proven false. Invariably this is a false dichotomy because it excludes an important third option: that insufficient investigation has been carried out. In which case, the wisest response would be to defer further argumentation pending the completion of further investigation.

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The Ad Hominem

I have separated out “ad hominem” from the above because strictly speaking, this is not a “logical fallacy” (i.e., a failure to reason properly). Rather, it is a rhetorical tactic.

So what does ad hominem mean? Well as most will already know, it means attacking someone’s character and not their argument: a discomfort anyone offering a remotely independent opinion – especially one that challenges the prevailing group-think – will quickly experience.

Many will be familiar with the meme “troll”. This label is commonly thrown at the person targeted by the ad hominem. When thrown at the unprepared, this acts as a very effective smokescreen. Normally it serves to fuzzify (dilute) your and other’s reactions. Coping strategies for making short shrift of ad hominems can now be found published online.

Any attack on the person advancing a given argument — as opposed to questioning the validity of the evidence or logic contained therein — qualifies as an ad hominem.

Like it or not, bad people often make valid claims, while good people often make invalid claims. Therefore it is necessary to separate the claim from the person. It is surely worth repeating … the validity of any argument has nothing to do with the character, social status, or wealth of those presenting it.

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Poisoning The Well

Here we have a premeditated example of the ad hominem. Somebody or some organization distributes unfavorable information that has been formulated or concocted to discredit, in advance, a person, group, or an ideology.

The strategy here is to force the target (person/group/ideology) onto the back-foot (to quote a Cricketing term) or onto the defensive, with the intention of keeping them there.

Those on the receiving end of this tactic should not devote any time or energy into justifying their existence, or explaining their motives, reasons, or past actions. Quite the contrary, the best response is to immediately and confidently go on the offensive.

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Formal and Informal Fallacies

Note that this blog post will treat categorization and taxonomy as equivalent. Most people are familiar with categories. What about taxonomies?

Within any given domain (e.g., populations of mechanical devices, digital cameras, edible crops, birds, fresh water fish, etc., etc.) a taxonomy is a system of classification based on natural (mutual) relationships. Originating in France around 1805-15 (taxonomie) the more formal definition says taxonomy is the science or technique of classification.

As you might expect, fallacies can be categorized (i.e., structured with a taxonomy) in several different ways. We should also acknowledge that some fallacies stubbornly defy any categorization, while a few others can happily occupy two or three categories simultaneously. Wiggle room is always provided by our interpretation and circumstance.

The primary division is between formal fallacies and informal fallacies. This in turn is predicated upon the two types of argument available to us: deductive and inductive.

A formal fallacy is related to deductive arguments, while an informal fallacy is associated with inductive arguments. Therefore:

♦ formal = deductive;

♥ informal = inductive.

In ♦deductive reasoning you start with general statements before proceeding towards the specific. In other words you move forward towards a conclusion by making a series of logical inferences.

In ♥inductive reasoning you move in the opposite direction. You start out with a set of particular facts (conclusions) before seeking a generalized conclusion (presumption) that has been induced backwards from those facts.

In water-tight ♦deductive arguments, the truth of the premise guarantees the truth of the conclusion. Any deductive argument that fails this test is deemed fallacious.

♦Deductive arguments specifically exclude measures of probability. They are valid only when they string together a sequence of certainties. If any measure of chance exists, then the reasoning becomes a “formal fallacy”. There are many “good” arguments that fail this simple test.

In contrast, ♥inductive arguments do not need to be rigorous to qualify as “good”. Good inductive arguments only need to lend support to their conclusions. Even when their premises are true, a conclusion reached by inductive reasoning might not be.

Thus, conclusions can only be accepted when some measure of probability is offered. So, with ♥inductive reasoning true premises can only establish a conclusion that is probably true, but never unquestionably true.

Realize that all ♥inductive arguments, even the good ones, are ♦deductively invalid, and thereby “fallacious” in the strictest sense of the term. The premises of an inductive argument are not intended to entail the truth of the argument’s conclusion. By design, even the best inductive argument falls short of deductive validity.

In consequence, the terminology needed to distinguish ‘good’ and ‘bad’ ♥inductive arguments must be different to that used to distinguish between ‘good’ and ‘bad’ ♦deductive arguments. If this is not done then every inductive argument would end up being labelled bad or “invalid”. The terminology used is very simple. Good and bad inductive arguments are distinguished by the terms “strong” and “weak”.

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Common Inductive Fallacies

NOTE: The term DACOTBO is an abbreviation of the long-form Drawing A Conclusion On The Basis Of …”

  • Hasty Generalization: DACOTBO relevant but insufficient evidence;
  • Sweeping Generalization: DACOTBO applying a generalization too broadly (failing to consider exceptions);
  • Small Sample: DACOTBO too small of a sample to reasonably justify the conclusion;
  • Unrepresentative Sample: DACOTBO a sample that does not represent the group about which the claim is made;
  • Questionable Statistics: DACOTBO statistics that are false, misleading, biased, or irrelevant;
  • Questionable Use of Statistics: DACOTBO good statistics that are used to mislead, bias, obfuscate, and so on;
  • Suppressed Evidence (cherry picking): DACOTBO the suppression of evidence that would undermine or contravene the evidence and/or the conclusion one is supporting;
  • Questionable Analogy: DACOTBO an analogy in which two things, A and B, are relevantly dissimilar;
  • Guilt by Association: DACOTBO a faulty induction by analogy individual to individual (or group to individual);
  • Natural Fallacy: DACOTBO the belief that, because something is natural it is therefore good;
  • Is-Ought Fallacy: DACOTBO the belief that, because something is the case, it therefore ought to be.

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Taxonomy of Fallacies

Logical fallacies were first identified long ago, else Machiavelli would have had a hard time writing “The Prince”. The more difficult task, and one still tinged with contention, is how best to collate and categorize all these various fallacies: how best to form a robust taxonomy.


The most favoured/favored approach is to group them according to their relevance, ambiguity, and presumption.

Fallacies of relevance contain premises that are not relevant to the truth of the conclusion. Primary examples are: irrelevant appeals (to pity, fear, flattery, and to authority, etc.), ad hominems, and the false dilemma.

Fallacies of ambiguity manipulate language in misleading ways. Primary examples are equivocation and the “straw man” fallacy.

Arguments that commit fallacies of presumption contain false premises, and so fail to prove their conclusion from the get-go. Examples are “circular reasoning” and “questionable cause” (because A and B are regularly associated, then one must be the cause of the other » e.g., There are many Muslim terrorists so Islam must promote terrorism).

Even those of us who are strongly motivated to become aware of fallacies – how they crop up, and how they are used and abused – are going to find it very difficult to keep up that awareness “in the heat of the moment”. But any attempt made when sailing a sea of deceit is surely worthwhile.

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External Resource #1

For those who would like to study the taxonomy of all known fallacies then check out this resource I stumbled-upon while researching. It has no bells & whistles; it instead focuses on functionality. Called Fallacy Files dot org, I am including a screenshot of what I found.

Click on this graphic (the screenshot) and it will open the external resource []. Note that the nodes of the hierarchy contain active links. Just click on any node to reach a page offering a detailed explanation of that particular taxonomy node.

For your own convenience (to minimize use of the “back button”) I recommend you hold down your CTRL key when left-clicking so that you always open those informational pages in a new tab (or window – depending on your browser’s default). Hee-hee … Just remember to keep track of how many new tabs you’ve opened!  🙂

Taxonomy of the Logical Fallacies – Click to open and explore this Taxonomy

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External Resource #2

Online Presentation: LOGICAL FALLACIES – by Michael Leggs  [will open in new tab]

N.B. Due to code restrictions enforced by my blog hosting service I am unable to embed this presentation. This is a code restriction enforced so that no bad stuff “sneaks in” to spoil your enjoyment. 😀



  • Logical Fallacies – An Encyclopaedia of Errors of Reasoning |
  • McDonald, Nicholas; Scribble Preach (Blog) – How Not to Argue Like an Idiot… The 15 Most Common Logical Fallacies – Web. March 13, 2013.
  • Walker, Jim; List of Common Fallacies – Originated: 27 July 1997 (additions: 01 Dec. 2009).
  • Drake’s List of The Most Common Logical Fallacies |
  • Mercyhurst University (Erie, Pennsylvania) – Lectures on Plato |
  • Internet Encyclopaedia of Philosophy |
  • Smith, Tania Sona; Edu*Rhetor (Blog) – What Is Rhetoric – Web. January 2010.

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