Harry Geels: Five subtle guises of the argumentum ad hominem

January 28, 2025

_{This column was originally written in Dutch. This is an English translation.}

By Harry Geels

Discrediting another, the argumentum ad hominem, is a common fallacy that is disastrous for debates. This assassin has five covert variants, which everyone should get to grips with.

Not too long ago, I saw a LinkedIn post come across that blamed a political party (and its party leader) for a social problem. It was a demonstrably inaccurate analysis, mainly because of the claim that one Dutch party would be the main culprit of something not only here, but throughout the Western world. As this post quickly got over a thousand likes, I felt the need to post some nuances. Something I unfortunately do less and less, as time is a scarce commodity.

The post concerned a fine example of the argumentum ad hominem, the discrediting of another (person or organisation), with the intention of making that person's or body's arguments seem less reliable. In Graham' s argumentative pyramid, this form of debate ranks second lowest, just above an even more damaging form of debate: swearing. However, the big problem with the argumentum ad hominem is that there are subtle forms of it, which actually make this argument more harmful than swearing.

The overt argumentum ad hominem usually consists of making the opponent ‘smaller’ by pointing out, for example, wrong behaviour or past ‘wrong’ arguments. Sometimes someone's appearance is also pointed out. In the Dutch public debate, for instance, Geert Wilders‘ blond hair is sometimes compared to Donald Trump's, or Frans Timmermans’ build would not match that of a socialist. The more disastrous forms of the argumentum ad hominem, because less recognisable, come roughly in five guises.

1) Education

The first guise concerns education: the less educated you are, the less reliable your opinion is. Or conversely, the more completed studies, the more reliable the opinion is said to be. The latter case is also known as the argumentum ad verecundium. We live in a diploma society. If you do not have degrees, then arguments, however well formulated, do not count. Of course, we have to pass an aptitude test for certain professions. But we must realise that someone with a diploma is not necessarily proficient. After all, every person is influenced by ‘emotional and behavioural biases’, physical and mental deterioration, self-interest, and possibly even bribery.

2) Familiarity

The second subtle form of the argumentum ad hominem concerns unfamiliarity: the less well-known someone is, the more unreliable the opinion would be. Or conversely, the greater the fame, the more important her or his opinion. The latter case is also known as the ‘wrong appeal to fame’. Indeed, the more unattainable a celebrity, the more trustworthy it seems to become. The latter is due to the peculiar phenomenon that people do not tolerate clever people in their vicinity (‘Tall Poppy Syndrome’). Even the Bible made mention of this: ‘A prophet is not without honour, except in his own country, and among his own kin, and in his own house’ (Mark 6:4; Matthew 13:57).

3) Large organisations

Then there is the peculiar phenomenon of looking up to high-ranking executives of large corporates more than directors of smaller companies. This is again due to various biases, such as the ‘status bias’, the ‘halo effect’ and ‘prestige size effect’. Media often play a negative role here, for instance by interviewing top people from large corporates more. As an aside, getting a high-ranking position by no means always requires intellect, but often other qualities count, e.g. aggressiveness, perseverance or opportunism.

4) Top Voice

The fourth subtle form concerns a relatively new phenomenon: the algorithms of social media, which rank certain people on the basis of vague criteria, effectively degrading the (ordinary) opinions of others. LinkedIn has the dubious phenomenon of Top Voice. The criteria for this are unclear and many top voices use questionable arguments or illegally copy third-party articles in their posts. Therefore, another call for the release of algorithms.

5) Professional cordons sanitaire

The fifth disastrous form is similar to the first (diploma), but different in that here the driving force is not the public but the profession itself, which deliberately keeps ‘unqualified’ people out. A variant of this, for example, is the well-known ‘not invented here syndrome’, where a solution or opinion from outside the profession is ‘expertly’ discredited as not having been invented by itself. Incidentally, this phenomenon also regularly plays out between generations within the same profession.

To conclude

The argumentum ad hominem is a nasty but unfortunately common form of discussion, which also contributes greatly to the current polarisation. Besides the overt form, there are also more subtle variants. Getting to the bottom of the problem is the first step towards a solution. That solution, incidentally, comes not only from social media (for example, by abolishing the ‘Top Voice’ designation), but also from the users themselves. For example, ignore posts that contain some form of ad hominem, no matter how much they fit one's own agenda.

This article contains a personal opinion of Harry Geels

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