1.1 Who thinks logically? Intuitive logic

In the story of L. Tolstoy “The Death of Ivan Ilyich” there is an episode that is directly related to logic.

Ivan Ilyich saw that he was dying, and was in constant despair. In the painful search for some gap, he grabbed even his old idea that the rules of logic, always true for all, are not applicable to him. “That example of the syllogism, which he studied in Kiesewetter's logic: Kai is a man, people are mortal, because Kai is mortal,” seemed to him throughout his whole life only to Kai, but not to him. It was Kai - a man, in general a man, and it was completely fair; but he was not Kai and not a human at all, but he was always a very, very special being from all others ... And Kai is exactly mortal, and he is right to die, but to me, Vanya, Ivan Ilyich, with all my feelings, thoughts, - this is another matter to me. And it cannot be that I should die. That would be too terrible. ”

The course of thoughts of Ivan Ilyich was dictated, of course, by the despair that gripped him. Only it can make us assume that the right thing always and for everyone suddenly turns out to be inapplicable at a particular moment to a certain person. In the mind, not covered with horror, this assumption ns may even arise. No matter how undesirable the consequences of your reasoning are, they must be accepted if the initial assumptions are accepted.

Force of speech

Reasoning is always coercion. Reflecting, we constantly feel pressure and lack of freedom.

It depends on our will on what to stop your thought. At any time, we can interrupt the thinking that has begun and go on to another topic.

But if we decide to hold it to the end, we will immediately fall into the net of necessity, which is higher than our will and our desires. By agreeing with some of the statements, we are forced to accept the fact that they flow from them, regardless of whether we like them or not, contribute to our goals or, on the contrary, hinder them. Having admitted one, we automatically deprive ourselves of the possibility of asserting another, incompatible with what has already been admitted.

If we are convinced that all metals conduct electricity, we must also recognize that substances that do not conduct electricity do not belong to metals. Having assured ourselves that every bird flies, we are forced not to consider chicken and ostrich birds. From the fact that all people are mortal and Ivan Ilyich is a man, we are obliged to conclude that he is mortal.

What is the source of this constant compulsion? What is its nature? What exactly should be considered incompatible with the already accepted statements and what should be taken along with them? What principles underlie our thinking in general? Above these questions, the man thought for a long time. From these thoughts, a special science of thinking has grown - logic.

The ancient Greek philosopher Plato insisted on the divine origin of the human mind. “God created the vision,” he wrote, “and handed it to us so that we could see the Mind movement of the world in heaven and use it to guide the movements of our own mind.” The human mind is only a reproduction of the intelligence that prevails in the world and which we perceive through the grace of God.

The first detailed and reasonable answer to the question about the nature and principles of human thinking was given by the disciple of Plato, Aristotle. "The compulsory force of our speeches," he explained the existence of special laws - the logical laws of thinking. They are the ones who force them to accept certain statements after others and discard the incompatible with the accepted. “Among the necessary,” wrote Aristotle, “is the proof, because if something is unconditionally proven, then there can be no other way; and the reason for this is the original premise. ”

Stressing the unequivocal nature of logical laws and the need to always follow them, he remarked: "Thinking is suffering," because "if a thing is necessary, it is a burden to us."

With the work of Aristotle began a systematic study of logic and its laws.

It never stopped, but in the XX century. Particularly impressive results were achieved.

In the comedy of J.-B. Moliere, “The Doctor Involuntarily” there is such a dialogue:

Sganarelle. We, the great physicians, define the disease at first sight. An ignoramus, of course, would be at a dead end and would pile on you all nonsense, but I immediately got into the essence of things and declare to you: your daughter is mute.

Geront That's the way it is, but I would like to hear why this happened?

Sganarelle. Do me a favor. Because she lost the gift of speech.

Geront Well, but tell me, please, the reason why she lost it.

Sganarelle. The greatest scholars will tell you the same thing: because her tongue is not tossing and turning.

Geront And what do you see the reason that he is not tossing and turning?

Sganarelle. Aristotle would say about this ... a lot of good.

Geront Willingly believe.

Sganarelle. Oh, that was a great husband!

Geront No doubt.

Sganarelle. Truly great! That's so (shows) more than me. But we continue our argument ...

It is ridiculous, of course, to observe how an imaginary specialist tries to convince others of his high professionalism. It is clear that there is convincing inside out. But what kind of mistakes are made by the "reluctant doctor"? Can each of us not only laugh at his clumsy reasoning, but also point out those specific violations of the argumentation rules that are contained in them?

Three blunders are striking even a non-specialist.

The first is the double use of tautology, i.e. a repetition with a slight modification of the same instead of indicating the real cause ("your daughter is mute ... because she lost the gift of speech ... because her tongue is not tossing and turning"). This technique is often used to give the illusion of persuasiveness empty, empty speeches.

The second mistake is the substitution of the subject of discussion: first, the talk is about the disease, and then suddenly it switches to Aristotle. Such a departure from the topic of a conversation or a dispute is a common trick of those who avoid speaking on the merits.

And, finally, the third mistake is the use of the word “great” in two completely different senses, issued for the same one: “great husband” is first “an outstanding husband”, and then “a tall man”.

To detect such errors on the surface, in general, special knowledge is not needed. There is enough natural logic, those intuitive ideas about the correctness of the reasoning that we have in the process of everyday practice of thinking.

The weakness of intuitive logic

However, this intuitive logic is far from always successfully coping with the tasks that confront it.

Does a person reason correctly when he says: “If aluminum were a metal, it would conduct an electric current; Aluminum conducts current, does it mean metal? ”Most often they answer: correctly, aluminum is metal, and it conducts current.