Chronology of chemical discoveries. A brief history of chemistry. Development of ideas and concepts in chemistry Phlogiston theory year

Section 1. Formulation of scientific concepts
1.1 Introduction. Interpretation of concepts……………………………..….. 2
1.2 Term and terminology……………………………………………. ......7
1.3 Difference between scientific and non-scientific concepts……………………….….…8
1.4 Content of the concept……………………………………………………………….….. 10
1.5 Concept in the history of philosophy………………………………….…..... 14
1.6 Concept in formal logic……………………………………...15
1.7 Explication of concepts……………………………...……………………… 17
Section 2. Refutation of the phlogiston theory
2.1 Cleansing natural science from natural philosophical concepts……...21
2.2 Georg Ernst Stahl………………………..……………………….…23
2.3 Basis of the phlogiston theory…………………………………….…26
2.4 Lavoisier system…………………………………………………... …29
Conclusion…………………………………………………………………… …………..…38
List of references………………………………………………………..39

1. Formulation of scientific concepts

1.1 Introduction. Interpretation of concepts

Much attention in theoretical logic is paid to the concept. A concept is an idea expressed in a single word or phrase about the essential and distinctive features of an object or class of homogeneous objects. The transition from the sensory stage of cognition to cognition at the level of abstract thinking is characterized as a transition from the reflection of the world in the form of sensations, perceptions and ideas to the reflection of the world in concepts and judgments, inferences and, ultimately, scientific theories formulated on their basis.
Let us consider the differences between the concept as the initial form of abstract thinking and the idea as the “highest” form of sensory cognition. Sensory cognition is always, to one degree or another, connected with clarity and imagery. The concept is devoid of imagery; operating with such concepts as “goodness”, “decency”, “enterprise” is not associated with their expression in the form of visual images. Sensory forms of cognition reproduce an object in its individuality, while the concept captures the common features of a number of objects. And, finally, the features of liveliness, details that characterize the external side of objects and phenomena are reflected in the concept, while the internal features of objects, their essence, are given in the concept. In a word, a concept is a form of thinking that reflects objects in their general essential features. Concept - the unity of essential properties, connections and relationships of objects or phenomena reflected in thinking; a thought or system of thoughts that identifies and generalizes objects of a certain class according to certain general and generally specific characteristics for them. Concepts are “abbreviations in which we embrace, in accordance with their general properties, many different sensory things” (F. Engels 1), as well as non-sensory objects, such as other concepts. The concept not only highlights the general, but also dismembers objects, their properties and relationships, classifying the latter in accordance with their differences. Thus, the concept of “man” reflects both the essentially general (what is characteristic of all people) and the difference between any person and everything else.
In everyday life, and even in science, the meaning of the word “concept” may differ from its meaning in philosophy or formal logic.
A concept is considered composite if it is based on other concepts, and elementary otherwise (for example: “Elementary concepts of statistics”)
Concepts can be divided into abstract and concrete, and, in each of them, into empirical and theoretical.
A concept is called empirical if it is developed on the basis of a direct comparison of the general properties of a certain class of existing (available for study) objects or phenomena, and theoretical if it is developed on the basis of an indirect analysis of a certain class of phenomena (or objects) using previously developed concepts, concepts and formalisms.
A concept is called concrete if it refers to a specific object in the surrounding world, and abstract if it refers to the properties of a wide class of objects.
The name of any material object is at the same time a concrete empirical concept. Specific theoretical concepts include, in particular, state laws.
Abstract empirical concepts reflect an accepted style of thinking or judgment, for example: “In the context of logotherapy, the concept of the spiritual does not have a religious connotation and refers to the strictly human dimension of existence.”
Abstract empirical concepts include, in particular, the unwritten and sometimes rather vague code of conduct of any social group (often criminal or even criminal), which in general terms determines what actions are considered “right” or “wrong”). To see the difference between theoretical and empirical concepts, compare 2 phrases:
“The sentences... were handed down in accordance with the laws in force at that time.”
“Sentences... were handed down in accordance with the concepts in force at that time”
(the example is taken from - according to the author’s intention, in the latter case we can essentially talk about lawlessness).
Abstract theoretical concepts are accepted in physics, for example: “Let us proceed to the presentation of the basic concepts of classical mechanics. For simplicity, we will consider only a material point, i.e. a body whose size can be neglected...”
In more specific cases, the concept is considered specific (although it may remain completely theoretical), for example: “An electron is a stable elementary particle with a charge? 2.
There are concepts in the broad sense and scientific concepts. The first formally identify common (similar) characteristics of objects and phenomena and enshrine them in words. Scientific concepts reflect essential and necessary features, and the words and signs (formulas) that express them are scientific terms. The concept distinguishes its content and volume. The set of objects generalized in a concept is called the scope of the concept, and the set of essential features by which objects in the concept are generalized and distinguished is its content. So, for example, the content of the concept “parallelogram” is a geometric figure, flat, closed, bounded by four straight lines, having mutually parallel sides, and the volume is the set of all possible parallelograms. The development of a concept involves a change in its volume and content.
The transition from the sensory stage of cognition to logical thinking is characterized primarily as a transition from perceptions and ideas to reflection in the form of concepts. By its origin, the concept is the result of a long process of development of knowledge, a concentrated expression of historically achieved knowledge. The formation of a concept is a complex dialectical process, which is carried out using methods such as comparison, analysis, synthesis, abstraction, idealization, generalization, experiment, etc. A concept is a non-figurative reflection of reality expressed in words. It acquires its real mental and verbal existence only in the development of definitions, in judgments, as part of a certain theory.
In the concept, first of all, the general is highlighted and fixed, which is achieved by abstracting from all the features of individual objects of a given class. But it does not exclude the individual and special. On the basis of the general, it is only possible to isolate and recognize the particular and the individual. A scientific concept is the unity of the general, the particular and the individual, that is, concretely universal. Moreover, the general in a concept refers not simply to the number of instances of a given class that have common properties, not only to the set of homogeneous objects and phenomena, but to the very nature of the content of the concept, expressing something essential in the subject.
Interpretation of basic concepts is an interpretation, clarification of the meaning of basic concepts. There are theoretical and empirical interpretations of the concepts.
Theoretical interpretation is a logical analysis of the essential properties and relationships of interpreted concepts by revealing their connections with other concepts.
Empirical interpretation is the determination of the empirical meanings of basic theoretical concepts and their translation into the language of observed facts. To empirically interpret a concept means to find an indicator (indicator, referent) that would reflect a certain important feature of the content of the concept and that could be measured.
All variables - yesterday's categories, concepts and terms - are interconnected and only in this form can they form a scientific theory. The nature of the connection is conveyed by the term “dependence”. This means that two or more variables depend on each other in some way (and how exactly remains to be found out in the study), for example, the level and extent of theft may depend on class position in this way: the lower the class, the higher the level of theft or on the contrary (given that the rich steal big). The expression “the lower, the higher” precisely describes the nature of the dependence, the specific (up to percentages and coefficients) parameters of which are discovered only in empirical research.
General theoretical definitions and empirical definitions have their own strictly defined range of application, beyond which they lose their truth and cease to correspond to reality. The translation of general concepts into “operational” concepts or concepts with a lesser degree of generality is fraught with the danger of reducing a higher-order essence to superficial connections, to a less deep essence.
Methodologically, this leads to the fact that, firstly, particular methods of empirical research acquire self-sufficient significance: secondly, the results of the study take the form of abstract, meaningless definitions that reflect only superficial, individual connections of real phenomena; thirdly, the actual sociological aspect of the study is replaced by analysis at the level of special sciences.
If we adhere to the procedure of empirical interpretation of general concepts, then in this case the meaning of social research would consist (as often happens) in the verification and testing of hypotheses previously put forward on the basis of general concepts.
When, when comparing general concepts with empirical facts, their correspondence is discovered, then the researcher either has nothing more to do, or all that remains is to confirm the correctness of the generalizations contained in previously developed general concepts.
The empirical level of knowledge and empirical methods for obtaining it do not take the researcher beyond limited generalizations, which, at best, turn out to be the simplest abstractions reflecting any individual aspects of reality.
Real objects, buildings, things, people in experimental research are replaced by empirical referents - real signs that record the presence or absence of the property being studied in an object and act as the value of a variable.
Description of the experimental situation, development and description of the research instrument, operational definition of variables and indication of empirical characteristics (referents), compilation of the sample population and much more are included in the content of the empirical scheme of the research object.
The empirical scheme is a model of real interaction, a typical scheme of practical transformations of sets of real objects. Each element of the empirical scheme is compared not with one object, but with a class of objects. This means that the scheme corresponds not to a single specific situation existing at a given time and place, but to a type of such situations.
In an empirical study that covers many heterogeneous objects in different parts of the country and reveals what is typical, repeating, and natural in them, the function of an empirical scheme is performed by: the structure of the sample population (distribution of respondents by age, gender, nationality, profession or any other characteristics), the basis samples (list of sampling units), sample size (number of sampling units), structure of the general population (for example, structure of the manufacturing industry by type, type, industry, number of employees, their professional and qualification structure, etc.).
The empirical design of the research object is aimed at studying real facts. Facts are events that can be directly (empirically) observed. Such facts are called empirical. An empirical fact in science is expressed by a single judgment about a specific event. However, not everything that can be observed is a fact. Individual objects or actions are not facts. A fact occurs only when specific objects (or subjects), a specific method of their interaction (or relationship), a specific place and a specific time are indicated.
Without facts there is no science, because scientists observe many facts, discover their repeatability and derive patterns. Scientists are not interested in isolated facts, because they cannot be subjected to statistical processing.
1.2 Term and terminology
The word “term” (terminus) is Latin and once had the meaning “limit, boundary.” A term is a word or phrase that serves to unambiguously and accurately designate (name) a special, scientific concept in a certain system of special concepts (in science, technology, production). Like any common noun, a term has content, or meaning (semantics, from the Greek semantikos - “denoting”), and a form, or sound complex (pronunciation). Unlike all other common nouns, which denote everyday, everyday, so-called naive ideas, terms denote special scientific concepts.
The Philosophical Encyclopedic Dictionary defines the concept as follows: “A thought that reflects in a generalized form the objects and phenomena of reality and the connections between them by fixing general and specific features, which are the properties of objects and phenomena and the relationships between them.” A concept has content and scope. The content of a concept is the totality of the characteristics of an object reflected in it. The scope of a concept is a set (class) of objects, each of which has characteristics that make up the content of the concept.
Unlike ordinary everyday concepts, a special scientific concept is always a fact of a scientific concept, the result of a theoretical generalization. The term, being a sign of a scientific concept, plays the role of an intellectual tool. With its help, scientific theories, concepts, provisions, principles, and laws are formulated. The term is often a herald of a new scientific discovery or phenomenon. Therefore, unlike non-terms, the meaning of a term is revealed in a definition, a determination that is necessarily attributed to it. Definition (Latin definitio) is the formulation in a condensed form of the essence of the concept being termed, i.e., denoted by the term: only the main content of the concept is indicated. For example: ontogenesis (Greek on, ontos - “existent”, “being” + genesis - “generation”, “development”) - a set of successive morphological, physiological and biochemical transformations of the body from its origin to the end of life; aerophiles (Latin аеr – “air” + philos – “loving”) are microorganisms that receive energy only from the oxidation reaction of oxygen in the environment.
As we see, the definition not only explains the meaning of the term, but establishes this meaning. The requirement to determine what a particular term means is equivalent to the requirement to give a definition of a scientific concept. In encyclopedias, special explanatory dictionaries, and textbooks, a concept (term) introduced for the first time is revealed in definitions. Knowledge of the definitions of those concepts (terms) that are included in the curriculum of the disciplines is a mandatory requirement for the student.
A special concept (term) does not exist on its own, isolated from other concepts (terms). It is always an element of a certain system of concepts (system of terms).
Terminology is a set of terms within a certain professional language, but not a simple set, but a system - a terminological system. Each term in it occupies its strictly defined place, and all terms together are in one way or another, directly or indirectly interconnected or interdependent. Here are some examples of definitions that support this statement. “Serotonin is a biologically active substance from the group of biogenic amines; found in all tissues, mainly the digestive tract and central nervous system, as well as in platelets; plays the role of a mediator in some synapses and in the development of some allergic reactions.” “Chromosome nondisjunction is a disruption of the process of meiosis, or mitosis, consisting in the departure of homologous chromosomes or chromatids during anaphase to the same pole, which can cause chromosomal aberration.”
To understand the meaning of a term means to know the place of the concept associated with it in the system of concepts of a given science.

1.3 Difference between scientific and non-scientific concepts

All scientific concepts reflect (formulate) some static or changing objective, generally accepted, known reality. As a rule, defined in uniform coordinate systems (standards) of time and space, in magnitude and dimension (nature). For example, planet Earth, A.A. Ivanov, the value of a parameter at a moment in time, a change in something, the number of people in the theater, the size of an object, a chemical element.... Or they reflect the relationships of objects, their interaction (collision of balls, exchange of values, display something for something..). These concepts have a specific internal structure, comparative characteristics, and therefore specificity. As a rule, they are generally accepted and to some extent standard, because something can be objectively compared with them. It is from these concepts that any thought, scientific theory, dispute or discussion, norm of legal law, and other concepts that carries objective information should be built.
Non-scientific concepts reflect a non-obvious, non-generally accepted, non-relative, not fully defined unambiguously (not known) and non-standard, not defined in space and time, subjective reality (soul, conscience, usefulness, infinity, justice, beauty, honesty, decency, people , good, bad, warm, cold, normal, good, evil...). Nothing can be compared with these concepts; they are ambiguous and non-specific. Poems, horoscopes, quatrains of Nostradamus 2, psychological tests, speeches of politicians, hypnotic influence, autogenic training, etc. are built from such concepts. This is an essential part of the language of humanists, poets, and politicians. They have proven their viability in terms of their emotional or psychological impact on the subject. But the limit of their scientific applicability is limited by a low degree of specificity, the lack of a standard for this concept and a comparative characteristic (value), the lack of an unambiguous structure, spatio-temporal and cause-and-effect certainty. “You can’t build a house or a barn on such concepts.” They are unacceptable in use when it comes to issues affecting the vital interests of people and their associations. They must be absent in any way of knowledge (science), in a serious discussion, in the theory of law (the way of knowing justice), in the speech of “people's representatives” and in any speech that conveys thoughts that claim to be generally accepted actual reality, to certainty.
Nobody argues about the importance of precise formulation of concepts for science. Any concept reflects reality. Either subjective or objective. Consequently, all cause-and-effect relationships reflecting this reality must be present in the structure and evolution (variability) of the concepts themselves. The methodological cause-and-effect relationship of scientific concepts must include a methodology of cognition and a methodology of variability of objects that are identified by their concepts. The methodology of cognition must include a methodology for the interaction of an object that needs a conceptual definition and a person who formulates this object in the form of a concept. If the formulation does not trace the structure of the known reality, therefore there is no methodology for the formation of concepts and a methodology for cognition of this reality. The following conclusion suggests itself: until general, global dependencies in the interaction, evolution of objects and their properties are determined, similar dependencies in the evolution and methodology of concept formation will not be found. So far, neither the first nor the second has been found in the modern methodology of cognition. And there is no positive movement in science in this direction. The concepts scientific and non-scientific are mixed, there is no difference between them. Scientific concepts are often defined through non-scientific ones, relative through non-relative ones. The conceptual crisis, as a consequence and manifestation of the general crisis of the theory of knowledge, is obvious.
So-called “scientific concepts” are often not methodologically formed. The cause-and-effect structure of concepts is not visible, and the general patterns of their formation and variability are not general scientific. Let's not be unfounded.
For example, there are a number of formulations of the concept “science”. It is perhaps impossible to come up with a more “scientific” example for this concept.
SCIENCE is a special type of cognitive activity aimed at developing objective, systematically organized and substantiated knowledge about the world. (The newest philosophical dictionary, edited by E.V. Khomich)
Science, the sphere of human activity, the function of which is the development and theoretical systematization of objective knowledge about reality; (TSB)
Science - in sociology - is a social institution whose function is the production, accumulation, dissemination and use of new knowledge. (Social Sciences)
From the analysis of the above formulations, the following conclusions can be drawn about the formulated nature of this concept.
That is, science is a type of human cognitive activity in the production, accumulation and systematization of objective (reliable, justified) knowledge. (ed.).

The two main logical characteristics of a concept are its content and volume.
The content of a concept is the totality of essential (general and distinctive) features of a certain object conceivable in it. Denoting various concepts with capital letters of the Latin alphabet A, B, C..., and the features that make up their content with lowercase letters a, b, c..., we can symbolically write down the content of the concepts A=a1^a2^a3^...an, B=b1^ b2^b3^…bn and so on. Obviously, the more features included in the content of a concept, the richer (broader) it is in content. So, for example, of two concepts: “a convex quadrilateral with right angles” and “a convex quadrilateral with right angles and equal sides,” the second concept (“square”) is broader in content than the first (“rectangle”) by one attribute (“ equality of arms").
According to content, four pairs of concepts are distinguished: a) concrete and abstract; b) relative and absolute; c) positive and negative; d) collective and dividing.
a) Concrete and abstract.
There are objects in the world that have properties and between which there are relationships. Consequently, in the act of abstraction we abstract, separate a property from an object or a relationship from the objects to which they are inherent. Consideration of properties and relations in themselves, independently of the objects to which they belong or which they relate, is a characteristic feature of abstract thinking. This understanding of abstraction helps us understand what is meant by abstract and concrete concepts. Abstract are concepts whose elements of scope are properties or relationships. In other words, in these concepts it is not objects that are singled out and generalized, but their properties or relationships (for example, “justice”, “whiteness”, “crime”, “caution”, “inherence”, “paternity” and the like). Concrete concepts are those whose elements of volume are objects (for example, “chair”, “table”, “crime”, “shadow”, “music”, etc.). In abstract concepts, properties and relations do not turn into objects. They are considered as objects, which gives us the opportunity to compose sets from them and consider them as elements of sets that make up the volumes of concepts. Sometimes, based on concrete concepts, they form abstract concepts associated with them. For example, on the basis of the concept of “man” one can form the concept of “humanity”, the element of the scope of which will be the complex property “to be a person”. On the basis of such an operation, the famous ancient Greek philosopher Plato constructed such concepts as “chairiness”, “horseness”, which he calls ideas and which, in his opinion, serve as prototypes of things in the sensory world. Most abstract concepts, such as the concepts of “justice”, “truth”, “equality”, “brotherhood” and the like, are single concepts; since there is only one property of human actions “to be fair”, one property of judgments “to be true”, one relationship between people “to be equal” or “to be a brother”. Some abstract concepts are still general. Let's consider the concept of “color”. The elements of the scope of this concept are the following properties: yellow, blue, red and the like, that is, some simple properties of objects. Consequently, a concept can be abstract, but at the same time general, since its scope contains more than one element.
b) relative and absolute.
An absolute concept is a concept whose basic content contains only attributes-properties. Example: A square is an equilateral rectangular quadrilateral. The content of this concept includes only signs-properties. Therefore, a square is an absolute (irrelevant) concept. A concept is called relative if its basic content contains at least one attribute-relation (example: debtor, creditor, plaintiff, brother, mother, etc.). When working with relative concepts, one should take into account their specificity, that is, the presence of relationships in their content. This means that all the “places” left free by the relation, except one, must be filled with the names of objects - without this the concept will be incomplete.
c) positive and negative.
A concept is called positive if its main content contains only positive features. A concept is called negative if its main content contains at least one negative feature. Example: the concept “concept” will be positive, but the concept “autocracy”, if understood as a monarchy in which there are no truly representative institutions, will turn out to be a negative concept, since the attribute “absence of truly representative institutions” is negative. The division of concepts into positive and negative has nothing to do with moral or other assessments of concepts. Thus, the concept of “immoral act” is negative not because we morally evaluate it negatively, but because its content includes the negative attribute “lack of moral character.” The concept of “crime” is positive, since its content includes only positive signs: “prescribed by criminal law”, “public danger” and “being an act”.
d) Collective and separative.
This is perhaps the most important distinction between types of concepts, because the rules for working with concepts are directly related to the identification of these types. These types of concepts refer only to general concepts. Single concepts can be neither dividing nor collective. Elements of the scope of a concept can be of two types: 1) they can be single objects, 2) they themselves can be sets of objects. In connection with this division, two types of concepts are distinguished. A collective concept is a concept whose elements of scope themselves constitute sets of homogeneous objects. Example: The collective concepts include: “crowd”, since the elements of the concept “crowd” are individual crowds, which, in turn, consist of homogeneous objects - people; “library” - since the elements of the scope of this concept consist of homogeneous objects - books; parliament, collective, constellation, fleet and the like. A concept is called separative if the elements of its volume do not represent sets of homogeneous objects. Examples: Most concepts are divisive. Man, student, chair, justice, logic, crime and the like. It is easy to see that collective and disjunctive concepts should be treated equally. You just need to always be aware of what is actually an element of the scope of collective concepts. In the concept of “library”, the element of the concept’s scope is not books, but libraries. If they say that the library was flooded, this does not mean that every book perished in the water. An element of the scope of the concept “social class” is not individual people - bourgeois, peasants or workers, but large groups of people. And therefore, if they tell you that something is in the interests of such and such a class, this does not mean that it is in the interests of every worker, bourgeois, peasant. You also need to be aware of what is considered part of the scope of such concepts. For example, part of the scope of the concept “university” is this or that set of universities, and not these or those faculties of a given university. Here we should remember the previously made distinction between the relation of genus and species and the relation of part and whole. Many concepts can be used both in a divisive and in a collective sense. “Citizens of our state support the idea of private property” does not mean that every citizen of the state supports this idea. According to the author of this statement, citizens of our state generally support this idea. Here the concept of “citizens of our state” is used in a collective sense. “Citizens of our state are obliged to comply with the law” - in this statement we are talking about every citizen, that is, the concept of “citizens” is used here in a divisive sense.

1.5 Concept in the history of philosophy

In the approach to the concept in the history of philosophy, two opposite lines have emerged - the materialist, which believes that concepts are objective in their content, and the idealist, according to which the concept is a spontaneously arising mental entity, absolutely independent of objective reality. For example, for the objective idealist G. Hegel, concepts are primary, and objects and nature are only pale copies of them. Phenomenalism considers the concept as the last reality, not related to objective reality. Some idealists view concepts as fictions created by the “free play of the forces of the spirit” 3 . Neopositivists, reducing concepts to auxiliary logical-linguistic means, deny the objectivity of their content.
Being a reflection of objective reality, concepts are as plastic as reality itself, of which they are a generalization. They “... must also be hewn, broken, flexible, mobile, relational, interconnected, united in opposites in order to embrace the world.” Scientific concepts are not something complete and complete; on the contrary, it contains within itself the possibility of further development. The main content of the concept changes only at certain stages of the development of science. Such changes in the concept are qualitative and are associated with a transition from one level of knowledge to another, to knowledge of the deeper essence of objects and phenomena conceivable in the concept. The movement of reality can only be reflected in dialectically developing concepts.
By concept, Kant meant any general representation, since the latter is fixed by a term. Hence its definition: “A concept... is a general representation or representation of what is common to many objects, therefore, a representation that can be contained in various objects.”
The concept for Hegel is “first of all, a synonym for a real understanding of the essence of the matter, and not just an expression of any general, any similarity of objects of contemplation. The concept reveals the true nature of a thing, and not its similarity with other things, and therefore not only abstract generality (this is only one aspect of the concept, which makes it related to representation), but also the particularity of its object must find its expression in it. That is why the form of the concept turns out to be the dialectical unity of universality and particularity, which is revealed through various forms of judgment and conclusion, and in judgment comes out. It is not surprising that any judgment breaks the form of abstract identity and represents its most self-evident negation. Its form is A is B (i.e. not-A).”
The universal concept expresses not a simple abstract community, the sameness of individual representatives of a given class, but “the actual law of the emergence, development and disappearance of individual things.”

1.6 Concept in formal logic

A concept in formal logic is an elementary unit of mental activity, possessing a certain integrity and stability and taken in abstraction from the verbal expression of this activity. A concept is something that is expressed (or denoted) by any meaningful (independent) part of speech (except for pronouns), and if we move from the scale of the language as a whole to the “micro level”, then as a member of a sentence. To interpret the problem of the concept (in its formal logical aspect), you can use the ready-made arsenal of three areas of modern knowledge: 1) general algebra, 2) logical semantics, 3) mathematical logic.

1.7 Explication of concepts

One of the requirements of the logic and methodology of science is the certainty and unambiguity of terminology. And if you turn to essays on social topics, the first thing you will notice is that this requirement is ignored. All the basic concepts here are ambiguous, vague, unstable, or have generally lost all meaning, turning into ideological and propaganda fetishes. Look at even a small part of only professional (i.e. not at all the worst) essays on social topics, and you will find dozens of different meanings of the words “society”, “state”, “democracy”, “capitalism”, “communism”, “ideology” ", "culture", etc. People seem to use the same words and talk about the same things, but in fact they speak different languages that only partially overlap, and manipulate word-like phenomena that are usually devoid of intelligible meaning.
This state of terminology is not just the result of people not agreeing on word usage. The matter here is much more serious. There are many reasons that make this condition inevitable. I will name some of them. Phenomena that were not previously distinguished are differentiated. Attention is drawn to various aspects of the same phenomena. Changes occur in the objects of attention. Many people think about and speak out about social phenomena, and they all have different levels of understanding and different interests. People use the same words in different contexts and for different purposes. Many people deliberately obscure the meaning of the terms. In addition, logical processing of terminology requires special professional techniques and skills that almost no one possesses. Out of curiosity, look through reference books that provide definitions of social terminology. Take a closer look at them. And even without special education you can notice their logical squalor. But these definitions are created by experts! So what is going on in the heads of others about this?
To fight against this polysemy and vagueness of words by appealing to the requirements of logic and calls for unambiguity and certainty of words is an absolutely hopeless matter. No international body endowed with extraordinary linguistic powers is capable of establishing order here that meets the rules of logic. How many different kinds of dictionaries and reference and educational literature have been and are being printed in the world that strive for certainty and unambiguity of terminology, and the situation in world language practice does not change at all for the better in this regard. Quite the contrary, for the volume of spoken and printed texts on social topics has increased thousands of times compared to the last century and continues to increase, while the degree of their logical culture has decreased almost to zero.
Is it possible to overcome the difficulties associated with the uncertainty and ambiguity of linguistic expressions, which have become a common condition in the sphere of social thinking and speaking? In science, a special logical operation was invented for this purpose - explication of linguistic expressions. The essence of this operation is that instead of linguistic expressions characterized by the aforementioned uncertainty and ambiguity, the researcher, for his strictly defined purposes, introduces a kind of substitutes or duplicates of these expressions. It defines these duplicates quite strictly and unambiguously, and explicitly expresses their logical structure. And as part of his research, he operates with these kinds of duplicates or substitutes for expressions circulating in the language; one might say, he operates with explicates of familiar words. Usually in such cases they talk about clarifying the meaning of terminology. But here it is not enough to note the aspect of clarification, because explication does not reduce to clarification. In addition, clarification is some improvement of existing linguistic means, while in the case of explication something more serious takes place: the complete unsuitability of these expressions is recorded and duplicates and substitutes for them are introduced.
The task of explication is not to list in what different senses (meanings) this or that linguistic expression is used, and not to select one of these uses as the best (i.e., to select an object for the word) , but in identifying quite clearly the objects of interest to the researcher from some larger set of objects and securing this selection by introducing a suitable term. The peculiarity of the situation here is that the introduced term is not a completely new linguistic invention, but a word that already exists and habitually functions in the language precisely as a polysemantic and amorphous expression. Naturally, the question arises: why not introduce a completely new term? This is often done. But then this operation is not an explication. When explicating, the use of the old word has very serious reasons. In the case of introducing a completely new term, it seems as if we are talking about something else, and not about objects to which familiar words refer in one way or another.
For example, when I introduced the term “communism” as an explicate of this word in the wider spoken language, many readers advised me to invent another word, since everyone understands communism in their own way. But I still insisted on this particular word, since it directed attention precisely to the object that interested me and my understanding of which, different from philistine and ideological ideas, I wanted to present.
Explication strives to direct the reader’s attention to those objects about which the reader already has some ideas, but at the same time it strives to give such a turn to the reader’s brains as is necessary (according to the author’s conviction) for a scientific understanding of these objects. The main thing in this operation is precisely the turn of the brain that lies behind the definition of words, and not these definitions themselves, as such. So it is a mistake to consider explicates of words simply as one of the uses of polysemantic words in addition to existing meanings.
In the case of explication of concepts, the reader is informed of a new way of understanding an object, about which the reader has already accumulated some amount of knowledge; one might say, there is already an intuitive idea of the object. The task of the research is to, having explicated an intuitive idea of an object and relying on it, offer the reader something new that cannot be known without such logical work of the mind. So the reader should be prepared for the fact that in the subsequent presentation much will seem familiar and even banal to him, and treat this with patience and tolerance. The main difficulty in the field of social research is not to make some sensational discoveries of unknown facts, such as microparticles, chromosomes, genes, etc. in the natural sciences, but in seeing the significance of well-known and familiar phenomena, comprehending them and discovering in them the patterns of grandiose historical processes and huge human associations.
In texts on social topics, including those related to the field of science, special terms are used, as a rule, in a logically poorly processed or completely unprocessed form. In order for these texts to acquire any meaning, they need additional interpretations (interpretations) and inventions (in particular, what is called reading between the lines). The task of explication is to exclude this kind of interpretation and invention, which is different for different people, unstable, ambiguous, changeable. One of the requirements of the scientific approach to the objects under study is to make the texts meaningful in themselves, to read into them what, and only what they contain, without any interpretation or invention.
In practice, this is almost impossible or only marginally possible. This requires a well-developed logical theory, which does not exist, requires special education, which no one receives, and requires gigantic efforts. Suffice it to say that even if it were possible to carry out a completely logical explication of texts, the resulting texts would be tens and even hundreds of times larger in volume than the explicated texts. Operating with them would be impossible. And if we take into account the intellectual squalor of the overwhelming majority of such texts, then in general, as they say, the game is not worth the candle. And on top of that, the people who produce such texts are not interested in logical clarity and certainty - they have goals that have little in common with the desire for scientific truth.

2. Refutation of the phlogiston theory
2.1 Cleansing natural science from natural philosophical concepts

The ideas of ancient Greek natural philosophers remained the main ideological sources of natural science until the 18th century. Before the Renaissance, Aristotle's ideas dominated science. Subsequently, the influence of atomistic views began to grow,
first expressed by Leucippus 4 and Democritus. Alchemical works were based primarily on the natural philosophical views of Plato and Aristotle. Most of the experimenters of that period were outright charlatans who tried to obtain either gold or the philosopher's stone, a substance that gives immortality, using primitive chemical reactions. However, there were real scientists who tried to systematize knowledge. Among them are Avicenna, Paracelsus, Roger Bacon, etc. Some chemists believe that alchemy is a waste of time. However, this is not so: in the process of searching for gold, many chemical compounds were discovered and their properties were studied. Thanks to this knowledge, at the end of the 17th century, the first serious chemical theory was created - the theory of phlogiston.
In the works of chemists of the second half of the 17th century. Much attention was paid to the interpretation of the phenomena of combustion and calcination (transformation into “lime”) of metals. This attention is quite understandable and is related to the needs of expanding production, primarily the fuel problem. The development of the metallurgical and metalworking industries, glass production and other branches of technology has led to catastrophic destruction of forests in a number of Western European countries. The lack of wood fuel and especially charcoal, the only means at that time for the recovery of metals from ores, which was widely used in production, confronted scientists and practitioners with the task of finding ways to use fuel more economically and rationally. At the same time, the search began for substitutes for charcoal in metallurgical processes. Back in 1619, Dad Dudley (1599-1684) proposed using hard coal instead of charcoal in the blast furnace process. Therefore, metallurgical technologists and chemists who developed ways to implement this proposal studied combustion processes and fuel properties quite widely.
On the other hand, the rapidly developing metallurgical industry felt the need to rationalize production technology in other respects. In particular, the issue of large losses of metal that turned into scale during melting and heat treatment was discussed. Therefore, the process of calcination of metals and their reduction from oxides has been widely studied. In addition, metallurgists of the 17th century. faced the problem of extracting metals from low-grade ores. A scientific justification for processing such ores with minimal metal losses was required.
The development of ideas about the combustion and calcination of metals occurred in close connection with the teachings about the components of complex bodies. Against the general background of the dominance of many traditional remnants of the Middle Ages, scholastic dogmas and alchemical beliefs, these teachings often took on ugly forms. There was no single point of view on the question of the basic principles of bodies. Some chemists adhered to the doctrine of the three principles of spagyrics, while others recognized only the ancient Aristotelian doctrine of the four elements-qualities; most chemists of the 17th century. tried to reconcile both teachings, while inventing various hypothetical principles of things; fourth, finally, such as Boyle, expressed doubts about the validity of the teachings of the Peripatetics and Spagyrics, formulated new ideas, but were inconsistent in their application to explanations of chemical phenomena.
The essentially correct definition of the concept “element” given by Boyle found no logical development either by him or by his contemporaries. It remained unclear which substances should be considered true elements of bodies. That is why chemists could not, and did not want, to part with the old ideas about the elements and searched for ways to confirm these teachings, having at their disposal only the only means for decomposing bodies: the “universal analyzer” - fire.
The belief that during combustion and calcination bodies decompose into simpler components compared to the calcined body itself can hardly be blamed on the chemists of that time. They observed such decomposition every day, obtaining in the residue earth (ash) and, in the form of volatile products, water and some air-like substances, the nature of which was still unclear at that time. Naturally, they considered the calcination of metals as a special case of combustion with the formation of the same earth (“lime”) in the remainder. They also saw confirmation that upon calcination the metal decomposes into its component parts in the formation of smoke, for example in the case of the calcination of antimony through burning glass and impure metals. None of them was embarrassed by the fact that as a result of calcination, metals significantly increase in weight. This fact was considered as a secondary, side effect, not of great importance when interpreting calcination processes as metal decomposition. Any explanation for this fact seemed acceptable, as long as it did not contradict the basic concept. Boyle gave one such explanation, admitting that during the calcination of metals, fiery matter is added to them. And his point of view was accepted without criticism by the majority of chemists.
In such an environment, the activities of the founder of the phlogiston theory, G. E. Stahl, took place. The system of views he developed, based on those that had developed by the end of the 17th century. ideas about the constituent parts of bodies and the phenomena of combustion, as well as the phenomena of calcination of metals, soon received full and undivided recognition of chemists and for many decades established itself as the theoretical basis of chemistry.

2.2 Georg Ernst Stahl

Georg Ernst Stahl (1659-1734) in his youth studied medicine at the University of Jena, after which, having received an academic degree in 1683, he taught here as a privatdozent. In 1687, he was invited to the position of life physician to the Duke of Saxe-Weimar, and in 1693 he moved to Halle to the newly founded university as the second ordinary professor of medicine and chemistry (the first professor was F. Hoffmann, who will be discussed below). During his 22 years as a professor in Halle, Stahl trained many students, some of whom later became prominent scientists. They were all
etc.................

In the seventeenth century, the rapid development of mechanics began, which turned out to be fruitful for chemistry.

The development of mechanics led to the creation of the steam engine and marked the beginning of the industrial revolution. A man got a machine that seemed to be able to do all the hard work in the world. But the use of fire in the steam engine revived chemists' interest in the combustion process. Why do some objects burn while others don't? What is the combustion process?

Long before the 18th century, Greek and Western alchemists tried to answer these questions. According to the ancient Greeks, everything that can burn contains the element of fire, which can be released under appropriate conditions. Alchemists adhered to approximately the same point of view, but believed that substances capable of combustion contained the element “sulphur”. In 1669, the German chemist Johann Becher tried to give a rational explanation for the phenomenon of flammability. He proposed that solids consisted of three types of “earth,” and one of these types, which he called “fat earth,” served as a flammable substance. All these explanations did not answer the question about the essence of the combustion process, but they became the starting point for the creation of a unified theory, known as the phlogiston theory.

The founder of the theory of phlogiston is considered to be the German physician and chemist Georg Stahl, who tried to consistently develop Becher’s ideas about “fat earth”, but unlike Becher, Stahl instead of the concept of “fat earth” introduced the concept of “phlogiston” - from the Greek “phlogistos” - combustible, flammable . The term “phlogiston” became widespread thanks to the work of Stahl himself and because his theory combined numerous information about combustion and calcination.

The phlogiston theory is based on the belief that all combustible substances are rich in a special combustible substance - phlogiston, and the more phlogiston a given body contains, the more capable it is of combustion. What remains after the combustion process is completed does not contain phlogiston and therefore cannot burn. Stahl argues that the melting of metals is similar to the burning of wood. Metals, in his opinion, also contain phlogiston, but when they lose it, they turn into lime, rust or scale. However, if phlogiston is again added to these residues, then metals can again be obtained. When these substances are heated with coal, the metal is “reborn”.

This understanding of the melting process made it possible to provide an acceptable explanation for the process of converting ores into metals - the first theoretical discovery in the field of chemistry.

Stahl's explanation was as follows. The ore, which contains little phlogiston, is heated on charcoal, which is very rich in phlogiston. In this case, phlogiston is transferred from charcoal to ore, as a result of which the charcoal turns into ash, poor in phlogiston, and the ore turns into metal, rich in phlogiston.

Stahl's phlogiston theory met with sharp criticism at first, but quickly began to gain popularity in the second half of the 17th century. was accepted by chemists everywhere, as it made it possible to give clear answers to many questions. However, neither Stahl nor his followers were able to resolve one question. The fact is that most flammable substances (wood, paper, fat) largely disappeared when burned. The remaining ash and soot were much lighter than the original material. But chemists of the 18th century. this problem did not seem important, they did not yet realize the importance of accurate measurements, and they neglected the change in weight. The phlogiston theory explained the reasons for changes in the appearance and properties of substances, and changes in weight were not important.

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The theory of "phlogiston", its significance for the development of organic chemistry

From the second half of the 16th century, a new period in the development of chemistry began. Advanced scientists of that time came to the conclusion that chemistry should be studied as an independent field of natural science, regardless of its application for the purposes of alchemy or healing. Chemistry should not be considered the handmaiden of any art or profession, but an essential part of the great teaching of nature; Only under this condition can chemistry as a science achieve significant success. During this period, the first ideas about chemically pure, or individual, substance, about complex substances and their constituent parts, and about chemical elements as the limit of decomposition of all substances gradually begin to be established.

The accumulation of information about substances and their mutual relationships has made it possible to make two important generalizations:

1. On the constancy of many properties of a certain, or “pure” substance: impurity is a consequence of the admixture of other substances, and not the result of the influence of immaterial properties.

2. On the related relationships between certain substances: a given substance can be obtained only from some (and not from all) substances, and, conversely, these latter can be obtained from a given substance.

All this allowed the famous English scientist, physicist and chemist Robert Boyle (1627-1691) to express for the first time the idea of elements as the limit of decomposition of substances (“The Sceptical Chymist”, 1661). Having abandoned the idea of hypothetical “philosophical” elements as carriers of the qualities of substances, he came to the firm conviction that it is necessary to pay attention mainly to those constituent parts of substances that can actually be isolated and which, therefore, really exist. If these constituent parts cannot be further decomposed, then they should be called elements. Thus, the number of elements cannot be given a priori, but can only be established by experience.

However, Boyle's views gained recognition among chemists slowly and gradually, and the above conclusions became dominant only by the beginning of the 18th century. It took about another hundred years to finally establish the concept of elements as the final products of the decomposition of substances. There was still no criterion for judging which changes in substances should be recognized as combination and which as decomposition; therefore, complex substances could be considered simple, and vice versa.

From the end of the 17th and almost until the end of the 18th century, the phlogiston theory, put forward to explain the processes of combustion and oxidation in general, as well as reduction processes, reigned supreme in the minds of chemists. The phlogiston hypothesis was the first theory in chemistry and allowed for the generalization of many reactions. This was a significant step towards the development of chemistry as a science. In the 70s of the 18th century, the theory of phlogiston was refuted by the works of Antoine Lavoisier, thanks to which it was replaced by another - the oxygen theory of combustion.

Georg Ernst Stahl (1659-1734), German physician and chemist, creator of the phlogiston theory. Born October 21, 1659 in Ansbach. In 1673-1679 he studied medicine and chemistry at the University of Jena, where he became a private assistant professor and then a professor of medicine. From 1687 - court physician to the Duke of Sachsen-Weimar Johann Ernst. In 1694 he was elected professor of medicine at the newly opened University of Halle. He taught the basics of medicine and worked in a clinic, conducted extensive theoretical and experimental research in the field of chemistry. In 1715 he was invited to Berlin to serve as court physician to the Prussian king Frederick William I. He became president of the Medical College, the highest medical institution in Prussia. Thanks to his efforts, the Medical-Surgical College was founded in Berlin to train military doctors.

Stahl entered the history of chemistry as the author of the theory of phlogiston (from the Greek phlogistos, flammable). The term itself is found in Aristotle, and then in a number of doctors and chemists of the Middle Ages, but the first sketch of the doctrine of one of the “principles” of the macrocosm, the “combustible earth,” was given by Stahl’s predecessor Johann Becher.

Stahl's ideas were presented in numerous works - Foundations of winter technology, or the general theory of fermentation (Zimotechnica fundamentalis seu Fermentationis theoria generalis, 1697), Becher's example (addition to Becher's Underground Physics) (Specimen Becherianum, 1723), Foundations of dogmatic and experimental chemistry (Fundamenta Chymiae) dogmaticae et experimentalis, 1723). Stahl also owns works on mining, metallurgy, and assay art.

The creators of the phlogiston theory are considered to be German chemists Johann Joachim Becher and Georg Ernst Stahl. Becher, in his book Subterranean Physics (1669), outlined his very eclectic views on the constituent parts of bodies. These, in his opinion, are three types of earth: the first is fusible and rocky (terra lapidea), the second is greasy and flammable (terra pinguis) and the third is volatile (terra fluida s. mercurialis). The flammability of bodies, according to Becher, is due to the presence of a second, fatty, earth in their composition. Becher's system is very similar to the alchemical doctrine of the three principles, in which flammability is due to the presence of sulfur; however, Becher believes that sulfur is a complex body formed by acid and terra pinguis. In fact, Becher's theory represented one of the first attempts to propose something new to replace the alchemical doctrine of the three principles. Becher traditionally explained the increase in the mass of metal during firing by the addition of “fiery matter.” These views of Becher served as a prerequisite for the creation of the phlogiston theory proposed by Stahl in 1703, although they have very little in common with it. However, Stahl himself always claimed that the author of the theory belongs to Becher.

The essence of the phlogiston theory can be summarized in the following basic principles:

1. There is a material substance contained in all combustible bodies - phlogiston (from the Greek tslpgyufpzh - combustible).

2. Combustion is the decomposition of a body with the release of phlogiston, which is irreversibly dispersed into the air. The vortex-like movements of phlogiston released from a burning body represent visible fire. Only plants can extract phlogiston from the air.

3. Phlogiston is always combined with other substances and cannot be isolated in its pure form; The substances that are richest in phlogiston are those that burn without leaving a residue.

4. Phlogiston has negative mass.

Stahl's theory, like all its predecessors, was also based on the idea that the properties of a substance are determined by the presence in them of a special carrier of these properties. The position of the phlogiston theory about the negative mass of phlogiston (much later and not recognized by all supporters of the theory) was intended to explain the fact that the mass of scale (or all combustion products, including gaseous ones) is greater than the mass of the burned metal.

The process of firing a metal within the framework of the phlogiston theory can be represented by the following similarity to a chemical equation:

Metal = Scale + Phlogiston

To obtain metal from scale (or from ore), according to theory, you can use any body rich in phlogiston (i.e., burns without residue) - charcoal or coal, fat, vegetable oil, etc.:

Scale + Phlogiston-rich body = Metal

It must be emphasized that experiment can only confirm the validity of this assumption; this was a good argument in favor of Stahl's theory. The phlogiston theory was eventually extended to any combustion processes. The identity of phlogiston in all combustible bodies was substantiated by Stahl experimentally: coal equally reduces sulfuric acid into sulfur and earth into metals. Respiration and rusting of iron, according to Stahl's followers, represent the same process of decomposition of bodies containing phlogiston, but proceeding more slowly than combustion.

The first theory of scientific chemistry - the theory of phlogiston - was largely based on traditional ideas about the composition of substances and about elements as carriers of certain properties. Nevertheless, it was precisely this that became in the 18th century the main condition and the main driving force for the development of the doctrine of the elements. Engels evaluates the phlogiston theory as follows: “Chemistry... freed itself from alchemy through the theory of phlogiston.” It was during the almost century-long existence of the phlogiston theory that the transformation of alchemy into chemistry, begun by Boyle, was completed.

The phlogiston theory of combustion was created to describe the processes of firing metals, the study of which was one of the most important tasks in chemistry at the end of the 18th century. Metallurgy at this time was faced with two problems, the resolution of which was impossible without serious scientific research - large losses in the smelting of metals and the fuel crisis caused by the almost complete destruction of forests in Europe.

The basis for the theory of phlogiston was the traditional idea of combustion as the decomposition of a body. The phenomenological picture of firing metals was well known: the metal turns into scale, the mass of which is greater than the mass of the original metal (Biringuccio showed back in 1540 that the weight of lead increases after calcination); In addition, during combustion, gaseous products of unknown nature are released. The goal of chemical theory was a rational explanation of this phenomenon, which could be used to solve specific technical problems. Neither Aristotle’s ideas nor alchemical views on combustion met the last condition.

The phlogiston theory made it possible to give an acceptable explanation for the processes of smelting metals from ore, which consists of the following. The ore, which has little phlogiston content, is heated with charcoal, which is very rich in phlogiston; In this case, phlogiston passes from coal into ore, and phlogiston-rich metal and phlogiston-poor ash are formed.

The phlogiston theory - the first truly scientific theory of chemistry - served as a powerful stimulus for the development of quantitative analysis of complex bodies, without which it would have been absolutely impossible to experimentally confirm ideas about chemical elements. It should be noted that the statement about the negative mass of phlogiston was actually made on the basis of the law of conservation of mass, which was discovered much later. This assumption in itself contributed to the further intensification of quantitative research. Another result of the creation of the phlogiston theory was the active study by chemists of gases in general and gaseous combustion products in particular. By the middle of the 18th century, the so-called chemistry became one of the most important branches of chemistry. pneumatic chemistry, the founders of which Joseph Black, Daniel Rutherford, Henry Cavendish, Joseph Priestley and Karl Wilhelm Scheele were the creators of a whole system of quantitative methods in chemistry.

In the second half of the 18th century, the phlogiston theory gained almost universal recognition among chemists. Based on phlogiston concepts, a nomenclature of substances was formed; Attempts have been made to connect such properties of a substance as color, transparency, alkalinity, etc., with the content of phlogiston in it. The French chemist Pierre Joseph Maceur, author of the very popular textbook “Elements of Chemistry” and “Chemical Dictionary,” wrote in 1778 that the phlogiston theory “... is the clearest and most consistent with chemical phenomena. Differing from systems generated by the imagination without agreement with nature and "destroyed by experience, Stahl's theory is the most reliable guide in chemical research. Numerous experiments... are not only far from disproving it, but, on the contrary, become evidence in its favor." Ironically, Maceur's textbook and dictionary appeared at a time when the age of phlogiston theory was coming to an end.

It should be noted that in the historical literature there are serious disagreements in assessing the role of the phlogiston theory - from sharply negative to positive. However, it cannot be denied that the phlogiston theory had a number of undoubted advantages:

It simply and adequately describes experimental facts concerning combustion processes;

The theory is internally consistent, i.e. none of the consequences contradicts the main provisions;

The phlogiston theory is based entirely on experimental facts;

The phlogiston theory had predictive power.

Famous chemists of that time, Mikhail Lomonosov, Karl Scheele, Joseph Priestley, Henry Cavendish, looked for ways to isolate phlogiston from various substances, but were never able to discover it. Lomonosov, for example, assumed that phlogiston is a material body consisting of tiny particles (corpuscles).

Everywhere and everywhere chemists of that time were looking for traces of the mysterious phlogiston.

If coal burned, the chemist said: “All the phlogiston from the coal has gone into the air.” There is only ash left. When phosphorus, flaring up with a bright flame, turned into dry phosphoric acid, this was explained in the same way: phosphorus supposedly broke up into its constituent parts - into phlogiston and phosphoric acid. Even when the hot or wet metal rusted - and then the chemist saw the machinations of phlogiston: - Phlogiston is gone, and rust or scale remains from the shiny metal.

No one could really explain what phlogiston is. Others thought that it was something like a gas, while others said that phlogiston could neither be seen nor obtained separately, since it cannot exist independently, but is always associated with some other substance.

Some scientists at one time claimed that they had managed to isolate phlogiston in its pure form. But then they themselves doubted this and said: “Perhaps, what we took for pure phlogiston is not phlogiston at all.”

They did not know whether it had weight, like any other body, or whether it was weightless. Phlogiston seemed elusive and ethereal, like a ghost. But all the chemists of that time stubbornly believed in its existence.

Where did this strange belief come from? Anyone who observed the fire was struck by the fact that the burning substance was destroyed and disappeared. It is as if something is released from the ignited body and goes away with the flame, and in its place ash, ash, scale or acid remain. (We now call this combustion product acid anhydride.) The combustion seemed to destroy the substance, expelling from it something ghostly, elusive - the “soul of fire.” So it was decided that combustion is the disintegration of a complex flammable substance into a special fiery element - phlogiston - and other components.

During the development of the phlogiston theory, the difference in the properties of typical complex and changeable organic substances and typical simple and stable mineral substances, such as metals, oxides, acids, mineral salts, etc., was first noticed. However, according to the division of the material world established at that time into three kingdoms of nature - mineral, plant and animal, substances also began to be divided by origin into mineral, plant and animal substances. Chemists have not yet decided to combine the concepts of substances of plant and animal origin into one general concept of organic substances.

The division into plant, animal and mineral substances first appears in 1675 in Lemery’s chemistry course. Other chemists of that time were trying to substantiate this division and find the reason for the differences between substances of different origins. Thus, Becher believed that “the elements in the different kingdoms of nature are the same, but in plant and animal substances they are combined in a more complex way, and in mineral substances in a simpler way.” Another author of the phlogiston theory, Stahl, explains the difference in properties by different composition: “in mineral substances,” he says, “the earthy principle predominates, and in plants and animals the watery and combustible principle predominates.”

The chemistry of organic substances during the period of dominance of the phlogiston theory did not make noticeable progress either theoretically or practically. Organic substances were studied only for pharmaceutical needs or to improve technical processes, such as the dyeing process.

Despite the fact that the phlogiston theory misinterpreted the facts, it, especially at first, turned out to be useful for the development of chemistry. On its basis, it was possible to establish the related relationships of a huge number of substances and, using it as a guiding thread for chemical research, to correctly predict many chemical relationships of substances.

The experimental study of chemical reactions during this period first stood on solid ground.

Already by the middle of the 18th century, due to the accumulation of factual material, the phlogiston theory began to delay the development of chemistry as a science, preventing the explanation of new data. So, for example, in St. Petersburg in 1785 T.E. Lovitz discovered the phenomenon of adsorption of substances by coal from solutions, but, being influenced by the theory of phlogiston, he could not correctly explain this phenomenon, although he drew important practical conclusions from it.

The first argument against the theory of phlogiston was the discovery in 1748 by the brilliant Russian scientist M.V. Lomonosov's law of conservation of matter. In a letter to L. Euler dated July 5, 1748, Lomonosov wrote: “... all changes taking place in nature occur in such a way that as much as is added to something, the same amount is taken away from something else. So, as much substance is added to one body, the same amount will be taken away from another...” This law was established by Lomonosov on the basis of brilliant experimental work, among which his experiments on the oxidation of metals when heated in sealed vessels deserve special attention. Weighing the device on precise scales before and after the experiment, Lomonosov comes to the conclusion that after the chemical reaction of metal oxidation has occurred, the weight of the device does not change. With his experiments, Lomonosov refuted the results of similar experiments by R. Boyle. The latter's mistake was that at the end of the experiment he opened the sealed vessel; Air rushed into the retort, and the weight of the device increased. This led Boyle to the incorrect conclusion of the existence of weighty “matter of fire.”

Lomonosov's works, however, were not appreciated by his contemporaries, and only more than a hundred years later they aroused the surprise and admiration of the entire scientific world.

The final collapse of the phlogiston theory occurred as a result of the discovery of oxygen and the elucidation of its role in oxidation processes. Oxygen was discovered in 1774 by Scheele and, independently, by Priestley. However, these outstanding experimenters were both staunch supporters of the phlogiston theory (already refuted in their time) and therefore refused to be able to draw any truly scientific conclusions from their discovery. They considered the oxygen they received to be only “dephlogisticated” or “fiery” air, in which combustion occurs more intensely than in ordinary air. Neither Scheele nor Priestley were able to understand the enormous significance of the essential role they discovered for oxygen in chemical processes, despite the fact that they had convincing facts in their hands. Even after Lavoisier gave the correct explanation of the phenomena of combustion and oxidation in general, they continued to blindly defend their incorrect point of view. F. Engels, in the preface to the second volume of “Capital” by K. Marx, wrote the following about this historical fact: “Priestley and Scheele described oxygen, but they did not know what was in their hands. They "remained captive" to the phlogiston "categories that they found in their predecessors." The element that was destined to overthrow all phlogiston views and revolutionize chemistry was lost in their hands completely fruitlessly... Lavoisier, guided by this new fact, again subjected all phlogiston chemistry to research and for the first time discovered that a new variety of air was a new chemical element, that when In combustion, it is not the mysterious phlogiston that is released from the burning body, but this new element that combines with the body... And even if Lavoisier did not give a description of oxygen, as he later claimed, simultaneously with others and independently of them, he still essentially discovered oxygen he, and not those two who only described him, without even knowing what exactly they were describing.”

Thus, the merit of the final overthrow of the phlogiston theory belongs to Lavoisier, who, like Lomonosov, using a strictly quantitative research method, in his experiments (1772-1777) proved that the combustion process is not the decomposition of a substance, but the reaction of a substance combining with oxygen . Figuratively speaking, Lavoisier turned chemistry on its head.

theory phlogiston influence development chemistry

Literature

A. Azimov. A brief history of chemistry. Development of ideas and concepts in chemistry. M.: Mir, 1983. 187 pp.

A.N. Shamin. History of biological chemistry. Formation of biochemistry. M.: Nauka, 1983. 262 pp.

V.A. Volkov, E.V. Vonsky, G.I. Kuznetsova Outstanding chemists of the world. M.: Higher School, 1991. 656 pp.

P.M. Vigilant Critical look at the basic concepts of chemistry. Journal of the Russian Chemical Society named after. DI. Mendeleeva, 1996, volume 40, N3, pp. 5-25.

Rakov E.G. Substances and people: notes and essays on chemistry. M. "Akademkniga", 2003, 318 p.

Yu.I. Soloviev History of Chemistry (Development of chemistry from ancient times to the end of the 19th century. M.: Education, 1983.

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1.1 Introduction. Interpretation of concepts

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