Leonid Wassiljewitsch Rutkowski

Leonid Vasilyevich Rutkowski (born January 15 ^{. Jul} / 27. January  1859 ^greg. , † 10. March 1920 ) was a Russian logician and logic historian.

overview

Rutkowski took over the most important guiding principles from the Russian logician and philosopher Michail Iwanowitsch Karinski and developed them further. Like Karinski, Rutkowski tended to take a materialistic view of the laws and forms of thought. According to Rutkowski, the task of logic is to generalize the experience of each specific scientific discipline and to establish a scientific theory of evidence and investigation on it.

Rutkowski saw the main flaw in the works on logic that existed in Russia and other countries in the fact that one underestimated the content-related side of thinking and overemphasized the formal aspects separated from the content. According to Rutkowski, this alienation undermines the practical side of educating people to be able to correctly recognize the objective world of phenomena. According to his firm conviction, the fate of logic is closely linked to the realization of its main principle, namely the connection with reality, with the concrete objects and processes of life.

Sensation, perception and imagination, which provide the material for abstract thinking, as well as all forms of thinking itself - judgment , concept and conclusion - are for him subjective forms of the objective world. The forms of thought belong to the highest level of knowledge, but they do not arise of themselves and out of themselves, but on the basis of sensual knowledge . Rutkowski published his theoretical views on the logical laws and forms in a paper (1) in 1888 . Like Karinski, he assumed that conclusions were among the most important questions of logic.

Rutkowski shared Karinski's view of the nature of conclusions as a transfer of the definition from one object to another based on established identity. Rutkowski did not stick to Karinski's instructions mechanically, but developed them further. So he was z. B. the view that the transfer of the definition made solely on the basis of identity narrows the circle of conclusions and thus reduces the thought process. According to Rutkowski, there are not only relationships of identity between objects, but also relationships of subordination, dependency, coexistence, analogy, etc. a.

Since any form of thought , including inferences, reflects a form of objective relationships between objects in humans, according to Rutkowski, the transfer of definitions in the form of inferences must not only be based on identity, but also on all other forms of relationships between objects.

In his views on the nature of the conclusions, he assumed that all human knowledge, according to its genesis, can be divided into two categories:

• "1. Empirical knowledge, acquired by directly observing the perceived world, which is a simple expression of the facts observed, and

• 2. Inferred knowledge that is obtained from other previously acquired knowledge through a special mental process called inference. The conclusion is thus an act of thinking through which we arrive at new knowledge based solely on existing knowledge, independently of direct observation "(1, p. 4)

Conclusions

According to Rutkowski, any knowledge serves as an answer to one of the following questions:

a. To which object does the given definition belong, and b. what definition belongs to the given object?

So, ultimately, the job of inference is to find the answer to one of these questions. Rutkowski also tries to show ways to answer this question. He shows two procedures:

• 1. Since man knows that the given definition applies precisely to this object, it is permissible to claim that the same definition must also apply to any other object;

• 2. Since humans know that a certain definition applies to a certain object, it can be said that some other definition also applies to the same object.

If the task of inference is to infer new knowledge from what is already there, then obviously, according to Rutkowski, every inference procedure must consist of two parts:

• a. the knowledge from which the conclusion is drawn, and

• b. the knowledge inferred from the first.

For Rutkowski, the first knowledge is the basic knowledge and the second the inferred knowledge. It must be possible to infer the inferred knowledge from the basic knowledge by some logical procedure, and therefore, as he claimed, a third knowledge is required which legitimizes the extraction of the inferred knowledge from the basic knowledge. Rutkowski called this knowledge the well-founded knowledge.

In other words, Rutkowski is referring to the following three judgments that go with every conclusion:

• the basic judgment
• the inferred judgment
• the reasoned judgment

Rutkowski considered the reasoned judgment to be the most important part of reasoning, because its essence consists precisely in the decision whether it is justified to pass a judgment on the basis of another judgment.

According to Rutkowski, the task of every final proceeding is to find a new subject that justifies a definition that has been established in relation to the subject of the fundamental judgment. Therefore, Rutkowski divided all forms of logical inference into two main categories:

1. Inferences of the subjects

2. Inferences of the predicates

By contrasting the subject of the fundamental judgment and the subject of the inferred judgment in the conclusions of the first category, Rutkowski noted the following interrelationships between them:

A. They can represent separate objects, so that the predicate is transferred from one single object to another single object;

B. the subject of the fundamental judgment can be a single object, the subject of the conclusion a whole group of objects which also contains the object of the fundamental judgment. In this case, the predicate of the fundamental judgment is transferred from the individual objects to the group comprising them;

C. The predicate of the fundamental judgment contains the predicate of the inferred judgment

After Rutkowski had recognized the limitations of the traditional logic's classification of indirect inferences into syllogistic and deductive, he set up his own classification based on a number of Karinski's principles. In doing so he endeavored to grasp more completely than before the variety of types of classification of indirect inferences.

classification

Its classification included the following types:

• 1. The tradition as a conclusion due to the similarity, the identity and the conditional dependence

• 2. induction

• 3. the deduction

• 4. Production as a distributive syllogism.

In this case, thinking goes forwards in the substitution of a single definition by another single definition or goes from the already recognized definition to the one yet to be recognized. The prefix "pro" indicates the forward movement. The first modification of the conclusions of the productive type, according to Rutkowski, is that in which the reasoned judgment confirms the coexistence of certain properties or characteristics: if one is given, the others are also given. He considered the work of Georges Cuvier to be the most striking example of such a modification, who was able to reconstruct the entire organism using just the tooth of a long-extinct animal.

To this modification Rutkowski also included the disjunctive syllogisms, as well as the inferences based on the comparison in time (simultaneity), the functional and causal dependence, the commonality and equality of two objects with the same third. Rutkowski has broken new ground to clarify the essence of the conditional categorical syllogism. Contrary to tradition, he considered it possible in certain cases to use such modes of the conditional-categorical syllogism as the conclusion from the confirmation of the consequence to the confirmation of the reason and the conclusion from the negation of the reason to the negation of the consequence.

• 5. Subduction as a conclusion that is used in the classification of objects in the course of genetic and substantional explanations

If one replaces one definition in the object by another which contains the first in its content, then another, more comprehensive definition is assigned to this object. This fact is expressed by the prefix "sub". According to Rutkowski, such a conclusion exists when the object is defined by referring to the common term or to a group of objects to which it or to which it belongs. People also use this conclusion when explaining facts or phenomena they observe.

• 6. The education as a conclusion to the affiliation of an object to a certain class.

This type of inference occurs when the predicate of the inferred judgment is inferred from the broader predicate of the fundamental judgment. In the essence of the logical process, this conclusion is the direct opposition of the subductive inference. In the eduction, the predicate of the conclusion is a predicate part of the fundamental judgment, while in the subductive inferences the fundamental judgment determined the object by the characteristic which is part of the definition of the inferred judgment. That is why the idea of ​​inferring in the subductive conclusions goes from the less comprehensive definition to the more comprehensive one, while in the educational one goes the opposite way.

According to Rutkowski, however, the most important type of education are the probability inferences, by which he understands those cases of logical conclusions whose task is to determine expected events. With this classification of the conclusions, Rutkowski exceeded the two-part classification of induction and deduction for the first time in the Russian history of logic.

Works

• (1) The basic types of conclusions, St. Petersburg 1888 (russ.)
• Critique of the methods of inductive reasoning, 1899
• Elementarni uschebnik logiki primenitelno k trebowanijam rimnasischeskogo kursa, 1884

Web links

• WF Pustarnakow: University Philosophy in Russia (Университетская философия в России), Saint Petersburg 2003, ISBN 5-88812-184-3 pages 571-572
• Short biography , AZ-Library (Russian)