Critical thinking

Arguments must be convincing and, in order to convince, they must be valid—the minimum requirement of persuasion.

Western societies pride themselves on their access to information. Compared to our predecessors, we seem to be the most informed generation to have ever lived on Earth. However, paradoxically, the more data we have access to, the harder it is to determine what is true and what is false.

Critical thinking is not a cure-all, but it proves very useful in dealing with, clarifying, and solving some decision-making problems, as well as the thought and belief disputes which occupy our minds.

The appeal to ignorance (argumentum ad ignorantiam) is an error in thinking which argues that a conclusion is true because there is no evidence against it, or that a conclusion is false because there is no evidence in its favour.

A circular argument is an argument forming part of a thesis which has not been established, but still needs to be argued for.

In practice, people often accuse each other of making logical errors, but sometimes the accusation is false. Such an accusation is made by someone who does not understand what logical fallacies are and how they work, or by a manipulative person who takes advantage of the ignorance of those in the first category.

Almost a century ago, writer Virginia Woolf noticed people’s tendency to approach books “with clouded and divided minds, asking fiction to be true, poetry to be false, biographies to be flattering and history to chime with prejudices.”

From television stories to personal experiences, we live in a world where honesty seems to be an increasingly rare commodity and suspicion and scepticism become protective shields.

When it comes to conspiracy theories, the public quickly becomes polarised. On one hand, you have the “experts” who reel off reliable information with credible arguments from confirmed cases. On the other hand, there are the “uninformed,” completely disinterested in the subject or outright rejecting it as a myth.

Many news programmes, speeches, or press articles refer to at least one poll. When designed and conducted well, polls are an excellent means of measuring public opinion on a particular topic. Unfortunately, not all surveys are well compiled, relevant, representative, or honest.

The biased sample is a kind of unrepresentative sample, either for quantitative reasons (as is the case with the too-small sample), or for qualitative ones, when its structure does not represent the structure of the real population that is the object of the research.

When we consider that a conclusion is founded only if a lot of people consider it true, we fall into the trap of the argumentum ad populum or the appeal to popularity.

When what someone says can be interpreted in multiple ways, we are in danger of coming to an understanding which is different to their intended message.

The fact that we are able to anticipate most of the consequences of our actions is undoubtedly a blessing. However, we can also allow fear or over-cautiousness to make us anticipate events that are not likely to follow. This edges us toward a common error of judgement: the slippery slope.

In everyday life, whether we like it or not, we rely on the information provided by experts or specialists. However, no authority deserves blind trust. When we take someone's word for granted simply because that person is an authority, we make the logical mistake called "appeal to authority."