The multitude and complexity of information that we need to fit in short intervals into the right mental categories pave the way for the appearance of erroneous reasoning. When a conclusion is supported by very weak or even irrelevant arguments, the reasoning falls into the category called "non sequitur", i.e. "does not follow "11,or "irrelevant argument".
Election campaigns often use non sequitur sophisms such as: "Lying is harmful and immoral, and liars (candidate Y) should not be put in positions of state leadership, so vote for X." The conclusion is not logical, because the steps in the argument are missing, and those present are not relevant to the conclusion. The first statement is correct, the second is correct, but both are irrelevant to the conclusion. The logical conclusion of the first two statements would be: don't vote for liars. The missing steps in the logical fallacy argument - induced, but unproven - are: Y is a liar, the only honest candidate is X.
Types of non sequitur
"All people who have received Christian baptism will be saved. I am baptized, therefore I will be saved." Often the lack of argument for the conclusion means that it does not follow from a general premise, even if it is true. In this case, the premise is not true, but the conclusion may be true. This depends on the missing intermediate arguments.
"Believers go to church. George doesn't go to church, so he's not a believer." The denial of the antecedent does not necessarily result in the conclusion of the argument. To show that George is not a believer requires a series of probative arguments.
"Because X is right, Y is wrong,", "If it is love, God does not punish." The conclusion does not follow from the premise, and the error is constructed by proposing a false disjunction.
When and why non sequitur is used
Non sequitur errors occur most often due to a lack of critical thinking or sometimes attention. Other times, such sophisms are intentionally and biasedly constructed.
When it occurs unintentionally, a fallacy is usually the result of confusion or an automatism of the brain, which seeks to defend previously held beliefs. Our perception may change, our selection of new information becomes biased, the rigours of critical analysis may decrease, and so on.
When a lack of arguments is coupled with a desire to impose an idea, people resort to argumentative tricks that start from true facts or ideas, which they then link through faulty inductions to conclusions that seem correct. For this form of manipulation to be successful, it only requires that the interlocutors are uninformed or inattentive and naive.
Differences between non sequiturs and other sophistry
The "red herring" sophism, or irrelevant argument, is used with the aim of changing the subject of the discussion. This logical fallacy is similar to the non sequitur. Both are built on arguments that are irrelevant to the construction of the conclusion, except that the distracting reasoning changes the direction of the argument, whereas non sequitur continues, albeit irrelevantly.
Here's an example that differentiates the irrelevant argument from the non sequitur: "In the debate over intelligent design and evolutionary theory, religion is the red herring. An argument such as "Religion is concerned with finding meaning and significance in life, so the intelligent plan cannot be accepted" moves the subject from the need to evaluate by comparison the intelligent plan theory and the theory of evolution to an irrelevant discussion of the domain of knowledge circumscribed by religion.
In contrast, an argument such as "Religion is concerned with man's relationship to God, so it has nothing to say about the origin of life" is a non sequitur argument. It does not follow from the fact that religion is concerned with man's relationship with God that it has nothing to say about the origin of life.
The difference between non sequitur sophism and post hoc (false cause) sophism is a sensible one. Both one and the other reach conclusions that do not follow from their premises, only that the error of post hoc argumentation is built on a false causation. If an event X is followed by another event Y, it follows that Y is caused by X. The non sequitur error occurs rather because of a lack of logic and relevance in the relationship between argument and conclusion.
Here is an example: "M has changed his Orthodox religion to Catholicism. The day after he had a car accident. The accident happened because he renounced his right faith." In this case, the conclusion does not follow from the premise, but the fact that we have no argument that the accident was caused by the change of religion puts the example in the category of post hoc sophistry, not non sequitur sophistry.
Orice sofism formal are un non sequitur în concluzie. Chiar dacă uneori este mai greu sesizabil, toate erorile de gândire se înscriu în ceea ce înseamnă argumentul „nu decurge”: motivul pentru care nu decurge încadrează raţionamentul respectiv într-o categorie sau alta.
În articolul, „Cum se construiesc argumentele valide”, autorul Laurenţiu Moţ arată că, pentru a fi valide, argumentele trebuie să îndeplinească mai multe condiţii: Prima ar fi ca premisele să fie valide. Apoi, ipoteza argumentului trebuie să fie demonstrabilă pe bază de motive și de dovezi. În final, concluzia trebuie să derive din argumentaţie și să transforme ipoteza într-o teză. „Orice afirmaţie pleacă de la o premisă, din care rezultă o ipoteză. Această ipoteză urmează să fie testată, iar rezultatele se văd într-o aserţiune generală. La rândul ei, aceasta din urmă are în spate niște motive. Iar acele motive sunt susţinute de niște dovezi.2” Premisa duce la ipoteză, ipoteză – la motive, motivele – la dovezi, iar dovezile – la concluzie.
Non sequitur și arta umorului
Uneori, argumentul non sequitur este folosit pentru a schimba abrupt subiectul și pentru a da conversaţiei o tentă umoristică. Este chiar o figură de stil folosită în teatrul absurdului, adesea comică. Trecerea de la un non sequitur la altul poate crea efectul comic. Imposibilitatea audienţei de a intui șirul afirmaţiilor dintr-un spectacol și absurditatea lor adesea conduce la râsete.
Umorul de tip non sequitur funcţionează pe baza mecanismelor suprarealiste de combinare a elementelor aparent incongruente și disparate cu scopul de a deruta și de a surprinde. Acest efect ilogic funcţionează eliberând publicul de sub dominaţia raţionalismului și astfel, prin schimbările de imagini, personaje și stări de fapt, sala deseori izbucnește în râs3.
NOTES
- „ Richard Nordquist, «Non Sequitur (Fallacy)», ThoughtCo., 5 nov. 2019, https://www.thoughtco.com/what-is-a-non-sequitur-1691437 ” ↩︎
- „Laurenţiu Moţ, «Cum se construiesc argumentele valide», în Semnele Timpului, februarie 2020.” ↩︎
- „Cristina Modreanu, «Final de stagiune à la Dabija», în ArtAct magazine, nr. 125, 6 iulie 2011.” ↩︎
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