Ms Maritza Breitenbach holds a Bachelor of Science degree (cum laude), a Teaching Diploma and a Certificate in Small Business Management (magna cum laude), all from North-West University (NWU).  She also completed a Master’s degree (Philosophy in Biomedical Ethics) (cum laude) at the University of Stellenbosch (US).  Among her many diverse talents, she is also a published author, a seasoned entrepreneur, and an accomplished sculptor.

When logical reasoning goes wrong: Irrelevant and unacceptable arguments

In the third of her four-part series on critical thinking and logical reasoning skills, Ms Breitenbach examines the ruin of many a well-intentioned attempt at logical reasoning: irrelevant and unacceptable arguments.


This essay, the third in a four-part series, forges ahead in our quest to uncover helpful tools to hone our critical thinking and logical reasoning skills.  Such advance must inevitably rely and build on the foundation of the previous two essays.

In the first essay (May 2020 e-periodical issue 3), The Elements of Logical Reasoning, we discussed the technique(s) employed in recognising arguments and how to select them effectively out of a block or range of non-argumentative prose.  We defined an argument as a combination of statements (i.e. claims and beliefs) with a recognisable form – that is, where a statement or a group of statements, called the premise(s) – is intended to prove, substantiate and support another statement, the conclusion.

Constructing an argument was the focal point of the second essay (July 2020 e-periodical issue 4).  In it we identified and discussed the two fundamental principles that constitute the construction of a good argument.  These fundamental principles were identified as (a) the logical structure and (b) the truth of the supporting premises.  We concluded that the argument pattern, as well as the content of the supporting claims represent the core requirements for the construction of valid and sound arguments, as well as ones that are strong and cogent.

In instances where we fail to adhere to these two fundamental principles, we create invalid and weak arguments – and, in so doing, commit a fallacy.  Fallacies or fallacious arguments are broadly defined as misleading, deceptive, false, or erroneous.  To recognise these flawed arguments is not always an easy task – this is because they are often embedded in rhetorical patterns that obscure the logical connections between statements.

We can draw a distinction between formal and informal fallacies.  Formal fallacies refer to flaws in the logical structure (or pattern) of the argument.  It is sometimes also referred to as a ‘logical fallacy’ or non sequitur, which is the Latin expression for ‘it does not follow’.  Examples of non sequitur arguments are affirming the consequent and denying the antecedent.[1]  Informal fallacies, in contrast to formal fallacies, originate in a reasoning error quite apart from a flaw in the logical form of the argument.  Informal fallacies are often presented in flawless logical form with premises that are true, but these arguments are nonetheless suspect in some way or another.  It is these fallacies that form the central theme of this essay.

Introduction: Informal fallacies

Informal fallacies occur so frequently that they have been put into specific categories and have even been given identifiable names.  Some of these fallacies were identified by Aristotle, and date back to 384 – 322 BCE.[2]

Fallacies are divided into two broad categories – (a) those that have irrelevant premises, and (b) those that have unacceptable premisesIrrelevant premises have no bearing on the truth of the conclusion, and unacceptable premises are relevant to the conclusion, but are nonetheless questionable.

These flawed arguments are sometimes deliberately employed in an attempt to exploit the emotional, intellectual or psychological weaknesses of the audience.  However, they may also occur unintentionally, in which case it illustrates the deficient, inadequate or immature reasoning of the author.  In both cases, informal fallacies have the power to mislead in academic, political, legal and other high-stakes contexts; it creates a breach of trust and always calls the authority and intellectual integrity of the user – perhaps more aptly called the abuser – into question.

Aristotle identified three key elements of meaningful discourse – ethos, logos and pathos, which translates to credibility, logic and emotion.  Each of these elements make up one side of a rhetorical triangle.  Although the first of the elements (i.e. credibility) can be faked or forged, it simply is impossible to imitate or feign logicLogic can be seen as the bedrock of truth – the foundation on which one can build an unimpeachable argument.  Emotion also plays a vital part in the critical thinking toolbox – it is perhaps the most powerful force of the triangle, and it can be dangerous if it is unbalanced and unsupported by both credibility and logic (Shapiro, 2016).

A strong correlation exists between the occurrence of informal fallacies and our emotional, intellectual and psychological state.  This relationship, or phenomenon, creates a perfect framework to facilitate our discussion of fallacious arguments.

Emotions and logical fallacies

According to Festinger,[3] we experience cognitive dissonance when ‘cognitions, knowledge or items of information pertaining to oneself or one’s environment are in contradiction with one another.’  He additionally states that the ‘existence of dissonance (i.e. inconsistencies, discrepancies, and a lack of harmony) is psychologically uncomfortable’.  Richard Suinn (1965) published a study in ‘The Journal of General Psychology’ that proves a positive relationship between anxiety and dissonance.

The level of discomfort that is caused by cognitive dissonance, depends on:

  • our personal tolerance with regard to uncertainty and inconsistency;
    • the size of the disparity between opposing views (i.e. the more substantial the disparity the higher the level of unease);
    • the weight of our personal investment with regard to the issue at hand; and
    • the intensity of the meaning or value that we have assigned to certain ideas, notions or conduct.

According to the views espoused in Buster Benson’s (2019) book, ‘Why Are We Yelling? The Art of Productive Disagreement’, whenever confronted with cognitive dissonance, we revert to any one of four default brain patterns or voices in an attempt to alleviate our anxiety: (a) the voice of power, (b) the voice of reason, (c) the voice of avoidance, and, lastly, (d) the voice of possibility.

(a)     The voice of power

The voice of power wants to win the argument by shutting it down completely.  It simply refuses to accept alternative viewpoints.  This may, for instance, result in employing the begging the question fallacy (also called circular reasoning, or petitio principii).  These fallacies occur when an argument’s premises assume the truth of the conclusion, instead of supporting it.

For example:

‘The news is fake because so much of the news is fake.’[4]


‘We must obey the law because it is illegal to break the law.’

Another erroneous embodiment of the voice of power is the false dilemma (also called black-or-white reasoning or dichotomy) fallacy.  False dilemma arguments have the distinctive quality of presenting inaccurately, or even unscrupulously, either/or situations where, if one of the statements is rejected, then the onlooker/listener/recipient has to accept the other.  False dilemma fallacies are most often employed by extremists – it often occurs on a public forum where political and moral issues are dramatically polarised and debated.  Choices can seldomly be reduced to just two options – usually at least one additional (and logically valid) opinion would exist.  Typically, topics raised and presented in this manner would be aimed at addressing questions like,

‘Are you for or against abortions?’

or even involve, as a further example of this fallacy, the making of a statement like the following one uttered by George W Bush on 20 September 2001:[5]

‘Every nation in every region now has a decision to make.  Either you are with us, or you are for the terrorists.’

Closer to home, Eusebius McKaiser wrote an insightful article published in the Mail & Guardian (6 July 2018), addressing racial identity politics that falls perfectly into this category.  He used the example of Andile Mngxitama, president of Black First Land First, and Ernst Roets, Deputy CEO at AfriForum, who both believe that ‘all analysis can be reduced to one nifty concept or idea’.  In this regard, he wrote that:

‘[t]he only difference between a Roets and a Mngxitama is that the one reduces everything to the ANC’s apparent inherent evil, and the other reduces everything to race.’

This exemplar of oversimplification offered by the employment of black-or-white reasoning is not only fallacious, it also inadvertently disparages and silences other valid concerns or possibilities that exist in the in-between space.

(b)     The voice of reason

Alternatively, when confronted with conflicting ideas or situations that cause cognitive dissonance, we may default into the voice of reason.  When we take on this position, we may insist on hard evidence, but some claims are unfortunately often difficult, or even impossible, to verify by any acceptable means.  A typical fallacy associated with this type of reasoning is an appeal to ignorance, also known as argumentum ad ignorantiam.  An appeal to ignorance fallacy claims that a conclusion must be true if it has not been proven false, or false if it has not been proven true.

Consider this example: Reverend James Wilmot[6] worked in Warwickshire as a clergyman.  When he, after extensive research, could not find any books that belonged to Shakespeare, he questioned the validity of his writings, and concluded that William Shakespeare was not the beloved English playwright, and that instead it was Sir Francis Bacon.

This is the author Bill Bryson’s entertaining response to Wilmot’s theory:[7]

‘The statement cannot actually be refuted, for we know nothing about his incidental possessions.  But the writer might just as well have suggested that Shakespeare never owned a pair of shoes or pants.  For all the evidence tells us, he spent his life naked from the waist down, as well as bookless, but it is probably that what is lacking is the evidence, not the apparel or the books.’

Rising anxiety and the voice of reason may furthermore prompt us to employ the genetic fallacy.  The genetic fallacy occurs when a statement or claim is accepted or rejected purely on the grounds of its origin.  We may believe that it is common sense and perfectly valid to discard information that comes from suspect or undesirable sources.  But, based on this presupposition, imagine if the following Nobel Prize winners, namely Francis Crick,[8] a British molecular biologist, and the American biochemist, Kary Banks Mullis,[9] were rejected from consideration of this prestigious award purely because they supposedly were under the influence of narcotics at the time of their respective discoveries.  It is clear that sound and valuable propositions can come from questionable sources or undesired circumstances, and vice versa, of course.  In most cases, the source of an idea is irrelevant to its truth, and arguments should always be weighed on its merit and not solely on its source.

Similarly, the voice of reason may lead us to two other commonly used fallacies – an appeal to tradition and an appeal to popularity.  An appeal to tradition argues that a claim must be true just because it is part of a longstanding tradition, while an appeal to popularity argues that a claim must be true because a substantial number of people believe it.  These arguments may seem to be reasonable or well-reasoned, but are, in fact, fallacious.  Arguments must lean on strong evidence and the mere reference to popularity and tradition offers no real substance and is therefore not worthy of our acceptance.

(c)        The voice of avoidance

As the magnitude of cognitive dissonance rises, we may revert straight into the comforting voice of avoidance, which entirely steers clear of the discussion or issue at hand.  In this case the straw man fallacy is a perfect vehicle to employ.  Thisfallacy creates the illusion of having completely refuted or defeated an opponent’s position through the covert replacement of it with a different proposition and the subsequent refutation of that, i.e. the substituted (straw man) false argument.  These flawed arguments have frequently been utilised throughout history in polemical debate, and often occurs in highly charged emotional settings.  Consider this example:

‘The theory of evolution holds that humans come from chimpanzees.  But if that were true, then why are chimpanzees still around?  Shouldn’t they have evolved into humans by now?  I therefore believe that the theory of evolution is false.’

This argument typically portrays an incorrect claim of evolutionary theory and then argues against that inaccurate proposition, or the substituted straw man view.  The theory of evolution by natural selection does not claim that human beings evolved from chimpanzees – it holds that we share our closest common ancestors with chimpanzees.

Another avoidance tactic would be to appeal to the person – also called the ad hominem fallacy.  This type of argument attacks an individual with opposing views with the intention of diverting the discussion and discrediting their argument.  Look at the following statement:

‘[t]here has been no vision or inspirational leadership emerging from the First Person of the province, communities are losing hope and all the Premier does is wear a better outfit every day and shining like a lamp pole’.[10]

Notice that no supporting arguments are presented to support the ‘no vision or inspirational leadership’ statement.  The author offers neither meaningful discourse, nor a valid argument but regresses into the non-engaging decoy of the ad hominem fallacy.  Other examples of a response to the voice of avoidance may include slippery slope or hasty generalisation fallacies, which are both equally unacceptable.

(d)        The voice of possibility

Finally, the more mature and desired position that we may act upon when confronted with cognitive dissonance, is the voice of possibility.  This voice, in contrast to the other default positions that either avoid or refute conflicting viewpoints, is less reactive – it takes a breath and considers dissonance as beneficial for introspection, growth and deepened understanding.  It seeks out new perspectives, it enhances dialogue, and it creates a platform for logically valid and meaningful contributions.

Productive disagreement presupposes interest in conflicting ideas, which evolves into the discovery of more information – this, in turn, makes us feel more secure and may remove threats and reduce risk.  It may result in meaningful decision-making that enhances the possibility of concluding an agreement.  Furthermore, it deepens our connections with others, and it offers the opportunity to forge trust with one another.  The voice of possibility encourages us to operate with bravery and to truly engage with a collaborative mind-set.  It may even fill us with enjoyment and offer adventure, fun, and sometimes even awe – after all, Aristotle did suggest that argumentation is the art of seduction.


‘There is a great deal of human nature in people’ says Mark Twain.  This essay illustrates the undeniable link between the three legs of the rhetorical triangle – more specifically, between logic and emotion.  It also reminds us of our vulnerability to either commit, or succumb to, logically invalid and fallacious arguments.  Logical reasoning requires us to constantly reflect on our default reactions to conflicting ideas and to critically examine the justification of our assumptions, beliefs and values.

There are as many as fifty or more informal fallacies – knowledge of the most commonly occurring fallacies helps us to identify inconsistencies and errors in our own, or someone else’s reasoning.  I recommend a consideration of the following two sources – they offer an entertaining and wonderfully digestible summary of these frequently occurring fallacies:

I conclude this, the third of four essays on critical thinking and logical reasoning with an inspiring quote by Søren Kierkegaard, a Danish philosopher, theologian and poet:[13]

‘Whoever has learned to be anxious in the right way has learned the ultimate.’

[1]        See the previous essay in the July 2020 e-periodical issue 4 for more information on logical patterns.
[2]        In Aristotle’s ‘Sophistical Refutations’ (Sophistici Elenchi)he identified thirteen fallacies.  LibriVox offers a translated version of this book read by Geoffrey Edwards (2011), and it can be accessed by clicking on this link.  Further notable contributions to the field of logical fallacies are to be found in the works of the English philosophers Francis Bacon, John Stuart Mill and Jeremy Bentham.
[3]        The psychologist Leon Festinger first published ‘A Theory of Cognitive Dissonance’ in 1957.  It has, since then, become one of the most influential and researched theories in social psychology.
[4]        President Donald Trump during a press conference, 16 February 2017.  The full article, ‘An amazing moment in history: Donald Trump’s press conference’, by Stephen Collinson, a reporter for CNN Politics, can be accessed or retrieved at
[5]        Keeling, P. 2005. ‘The Bush Disjunction’ in ‘Philosophy Now’, available at
(visited 24 August 2020).
[6]        Wilmot (1726 – 1807) was the earliest proponent of the so-called, Baconian Theory.
[7]        ‘Shakespeare: The World as a Stage’(2016) at p. 180.
[8]        A joint winner – together with James Watson and Maurice Wilkins – of the 1962 Nobel Prize in Physiology or Medicine for the identification of the double-helix structure of DNA.
[9]        Also a joint winner – together with Michael Smith – of the 1993 Nobel Prize for Chemistry for his invention of the polymerase chain reaction (PCR), a simple technique that allows a specific stretch of DNA to be copied billions of times in a few hours and which makes cloning possible.
[10]      During December 2011, Cosatu’s Western Cape Provincial Secretary, Tony Ehrenreich, released this media statement in reference to the then Western Cape Premier Helen Zille.
[11] (visited 24 August 2020).
[12] of-rhetoric-and-logical-thinking (visited 23 August 2020).
[13]      Rosner, B. 2020. ‘Coping with coronavirus anxiety: four lessons from Søren Kierkegaard’.  ABC Religion & Ethics.  Available at (visited 24 August 2020).

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