Ad hominem is a shortened form of the Latin phrase argumentum ad hominem which translates to “argument to the man“. Simply put these are the attacks that are done on the opponent as a person instead of their point. This attack may come as a critique of the opponent’s character or a personal trait or motive [1, 2].
These personal attacks can sometimes be overt attacks as shown in Fig 1 or more subtle attacks to cast doubts about their character or personal attributes to discredit their argument as shown in Fig 3.
The objective of an ad hominem attack is to undermine the platform of the opponent without having to face and deconstruct their actual case.
Some examples of what qualifies as an ad hominem attack and what does not is demonstrated in Fig 1. As all rules, the ad hominem attacks rule also has an exception. That is when the character trait being attacked is directly relevant to the argument being made. A good example is; in a law case, if it is possible to prove that the witness of the crime is a pathological liar , it is not an ad hominem attack because the truthfulness of the witness is critical for the authenticity of the witness’ account of the crime. But when the said trait has no relevance to the point that is being argued about, then it becomes an ad hominem attack. A good example of this is the part of discussion shown in Fig 3. Mr. Senarath calling me Mr. Ego is an ad hominem attack given that the existence of my ego or the implied size of it is irrelevant to the subject that is being discussed.
Ad hominem, being a popular choice for people who are unable to properly argue, has branched into a three specific types; Tu quoque, Bulverism, and Guilt by Association. Now, in the future I might expand on these individual sub-fallacies if I have time. But until then, I shall give you a brief introduction to each of them here.
Again, meaning of Tu quoque comes from Latin. It means “you also”. This is the formalization of the saying “pot calls the kettle black”. It is used when a person raising a point has spoken or acted in a way that is criticized by the claim that is being made. An example for this is; people criticizing Leonardo DiCaprio’s efforts to stop global warming because “He uses jets and expensive cars”.
What one must understand here is the only real outcome of a Tu quoque is to find the person to be a hypocrite. But essentially, that in no way invalidates his or her argument. In the example, Leonardo DiCaprio might be a big hypocrite to use his private jet to fly to get an award given to him for his efforts of preserving the nature, but it does not invalidate the arguments he make or the research that he presents. No matter whether Leonardo DiCaprio is a hypocrite or not, global-warming is happening.
This is also called Ad hominem circumstantial. As the name suggests, this is an attack on a person claiming that the person is in a certain circumstances such that s/he is anyway disposed to take a particular stance in an argument. Thus the Ad hominem circumstantial is an attack done on the source of the argument. This is a fallacy because even when a person has a disposition to take a certain viewpoint, that does not automatically invalidate the legitimate points that person raises. Again take the example of the global warming. A climate scientist may be voicing his/her opinion and warns of the impending doom of the planet. A conservative person that hears and sees this might say “Well, he/she will say that anyway because if not he/she will be out of a job soon”. While the scenario that is being painted by the conservative person here is true, it does not invalidate the legitimacy of the actual scientific facts raised by the scientist. Thus, this is an example for Ad hominem circumstantial. It is worthy to note that Bulverism can be said to have another parent fallacy as well (other than Ad hominem). That is the genetic fallacy. If and when I get some time, I will write about that as well. But in short, genetic fallacy is when someone claims an argument to be faulty simply because it came from a certain source.
Guilt by Association
This is also called Association fallacy or Shill fallacy. Simply put, this is the variation of the Ad hominem fallacy where one attacks the opponent by bringing up another person or a group that is disliked by many but holding the same opinion on the particular matter that is being argued about as one’s opponent. The simplified structure is; A makes the claim C. B, hearing this, points out that the well hated group G also holds the claim C to be true. Thus B moves to claim that A is associated with the group G as well and thus should be shunned for all the undesirable actions of the group G. Say, Alice claim that there should be stronger immigration laws in her country. Then Bob points out that the fascist alt-right has the same idea about immigration. Bob extends this note by claiming that given Alice has the same viewpoint as the fascists, now Alice is a fascist as well. That is clearly Ad hominem guilt by association. A similar real life story is how previously secular USA came to use “In god we trust” just to distance themselves from the communist plague who were also, for different reasons, secular. But that is a big discussion topic by itself, so I will not say anything else about it here. Now this particular fallacy should be pointed out with extreme care or you might end up being guilty of one of the previous two subsection types of Ad hominem.
I can give an example from a series of recent arguments that I had on Facebook with some of my friends. The background is the fact that they have teamed up with the historically militant communists to destroy private medical universities in Sri Lanka. Now, in this case, I can point them out as affiliating with communists, colluding with them, and adopting some of their ideals. BUT I have not accused any of them of planning a bloody rebellion as the communists tend to do historically and otherwise. Each time I made the said point, I was careful to either raise it as a question “are you suggesting a bloody rebellion?” or to distinguish them from the actual communist blight, for example “Your compatriots’ bloody rebellions…”, “Your ally’s…”, “Your friend’s….”. This way, I am never accusing my friends of attempting a rebellion. The question approach gives them an opportunity to answer first unlike in the case of an outright claim of guilt by me. The second approach distinguishes that they have not adopted some of the extremist, stupid, and anti-progress ideas of their “friends” as of yet.