Ignorance is dangerous, but when it is clothed with apparent rationality it is even more so because it eludes logic and leads us to accept foolish ideas. Argumentum ad ignorantiam transforms ignorance into its battle horse, confuses us and makes us accept sharp judgments that claim to become absolute truths.
Everyone saw one of the most famous examples of the ad ignorantiam fallacy: the hearings of Senator Joseph R. McCarthy in the early 50s. In a series of televised hearings, McCarthy accused many innocent people of being Communists, in the midst of a "witch hunt" atmosphere in which unfounded but very harmful accusations were often made.
McCarthy always appeared with a bulky briefcase apparently full of documents with information about the accused. But in most cases he presented no - or very little - actual evidence. In fact, he is said to have had 81 stories of people he considered communists, but at one point he said, referring to case 40: it is nothing that would allow him to deny his ties with the Communists ”.
In that case McCarthy resorted to an argumentum ad ignorantiam, a Latin expression meaning "appeal to ignorance". Rather than prove his claim by providing evidence, McCarthy based his allegation on the lack of evidence to refute it.
The mistake of appealing to ignorance is particularly dangerous because it can persuade people of the most eccentric ideas or make the most unsuspected accusations, just because no one can prove otherwise.
Unfortunately this type of topic is very present in our daily life, both in politics and in the media and in informal discussions with friends. Learning to detect the ad ignorantiam fallacy is essential to avoid falling into its net.
Cos'e l'argument to ignorance?
The appeal to ignorance or fallacy ad ignorantiam consists in defending an idea simply by saying that there is no evidence to the contrary. In practice, something is assumed to be true or false just because the interlocutor cannot present convincing evidence to the contrary.
It is known as argumentum ad ignorantiam because these people do not base their speech on a more or less profound knowledge of the subject but precisely on ignorance about it. They are not based on knowledge, but on its absence.
Basically, this error consists in assuming that since X cannot be refuted, then X is true. Although its opposite is also valid, that is, since X cannot be proved, X is false.
There are many examples of argumentum ad ignorantiam. Some might say that since intelligent life has not been proven outside the Earth, then it does not exist. Or that since cell phones have not been shown to cause cancer, they are absolutely safe. There are also those who assume that, if no one complains about the situation, it is because the situation is satisfactory, deducing that those who remain silent consent (law of silence-assent), although there may be a thousand reasons not to openly express a complaint, for example fear of possible retaliation.
Indeed, the ad ignorantiam fallacy systematically violates the principle of sufficiency, according to which the absence of evidence that refutes a claim does not constitute sufficient proof of its truthfulness, just as the absence of supporting evidence is not sufficient to disprove it.
The trap set by the appeal to ignorance
In logic there is the principle onus probandi or burden of proof, according to which the person who breaks normality has the duty to prove his claim. Basically, if someone makes an accusation, they have to prove it. And if someone claims to introduce a new truth or question something, they too must provide evidence to support their arguments.
However, the ad ignorantiam fallacy ignores this principle. The person who appeals to ignorance appropriately evades this burden by placing it on the shoulders of the interlocutor. He merely launches an idea, often clothed in feeble truth, challenging others to prove otherwise, when in reality it would be his duty to provide valid arguments in support of his claim.
Thus, the person who resorts to the ad ignorantiam fallacy manages to put us against the ropes, trying to force us to prove or refute his claims, because it is the only defense he leaves us. If we do not have sufficient knowledge of the subject, it will be difficult for us to propose convincing arguments or defend ourselves against accusations.
In practice, the person asks us to respond with logic when he himself is unable to follow the logic or provide an argument. He asks us to play cleanly when he has already cheated us from the start.
Come to disprove an argument for ignorance?
First of all, it is important not to start arguing about the topic in question because it increases the chances of emotions taking over and the discussion derails. A fallacy ad ignorantiam is not refuted, rather the lack of arguments is highlighted. Sometimes it is enough to point out that "the absence of evidence proves nothing".
In fact, the Greek philosopher Sexto Empirico recommended suspending dialogue and any kind of judgment, when a discussion starts from false premises and there is not enough evidence that can prove or refute a claim. In this way we will avoid falling into the trap of argumentum ad ignorantiam and getting involved in useless discussions that waste our energies unnecessarily.
After all, life is uncertainty and discovery. There are many issues that cannot yet be rejected or accepted categorically. And we have to learn to live with that. Just as we must learn to relate to people who make unfounded accusations using ignorance as a flag.
