Science can be organized into major scientific disciplines, including: mathematics, chemistry, biology, physics, mechanics, computer science, psychology, optics, pharmacy, medicine, astronomy, archeology, economics, sociology, anthropology, linguistics. The disciplines are distinguished not only by their methods or their objects, but also by their institutions: journals, learned societies, teaching chairs, or even their diplomas.
(The scale of the Universe mapped to branches of science and the hierarchy of the sciences.)
Several disciplines classification axes exist and are presented in this section:
- axis of the finality: basic sciences (ex: astronomy) / applied sciences (ex: sciences of the engineer)
- axis by nature (categories). After a ranking of 2, then 3 in the history of science, the practice now retains four categories:
- formal sciences (or logico-formal sciences);
- the physical sciences;
- life sciences;
- social sciences.
- methodological axis.
On the other hand, the term “pure science” is sometimes used to categorize the formal sciences, built on purely abstract entities. It is about mathematics and logic.
The social sciences, like sociology, are concerned with the study of social phenomena; the latter, like physics, deal with the study of natural phenomena. More recently, some authors, such as Herbert Simon, have evoked the emergence of an intermediate category, that of the artificial sciences, which deals with the study of systems created by man – artificial – but which exhibit a certain behavior. independent or relatively human action. This is for example the engineering sciences.
We can also distinguish the empirical sciences, which concern the study of phenomena accessible by observation and experimentation, of the logico-formal sciences, such as logic or mathematics, which concern purely abstract entities. Another way of categorizing the sciences is to distinguish the basic sciences, whose primary purpose is to produce knowledge, applied sciences, which are primarily aimed at applying this knowledge to the solution of concrete problems. Other categorizations exist, including the notion of exact science or hard science. These last categorizations, although very common, are much more questionable than the others, because they carry a judgment (some sciences would be more exact than others, certain sciences would be “soft”.
There is also a classification of science using the model of Russian dolls.
In general, no categorization is completely exact or fully justifiable, and the epistemological areas between them remain unclear. For Robert Nadeau: “we generally recognize that we can classify [the sciences] according to their object (…), according to their method (…), and according to their purpose”.
Basic and applied sciences
The “basic sciences” aim primarily at the acquisition of new knowledge. This primary classification is based on the notion of utility: some sciences produce knowledge in order to act on the world (the applied sciences), that is to say in the perspective of a practical objective, while others (the basic sciences) aim primarily at the acquisition of abstract new knowledge. Nevertheless, this limit is unclear. Mathematics, physics, chemistry, sociology or biology can thus be basic as well as applied, depending on the context. Applied sciences (which should not be confused with technique as the application of empirical knowledge) produce knowledge in order to act on the world, that is, from the perspective of a practical goal, economic or industrial.
Some disciplines, however, remain more entrenched in one area than in another. For example, cosmology is an exclusively fundamental science. Astronomy is also a discipline that is to a large extent fundamental science. On the contrary, medicine, pedagogy or engineering are essentially applied sciences (but not exclusively). Applied sciences and basic sciences are not compartmentalized. Discoveries from basic science find useful purposes (eg laser and its application to digital sound on CD-ROM). Similarly, some technical problems sometimes lead to new discoveries in basic science. In this way, research laboratories and researchers can carry out applied research and basic research at the same time. In addition, basic science research uses technologies derived from applied science, such as microscopy, computational capabilities of computers through numerical simulation, for example.
On the other hand, mathematics is often regarded as something other than a science, partly because mathematical truth has nothing to do with the truth of other sciences. The subject of mathematics is indeed internal to this discipline. Thus, on this basis, applied mathematics often perceived more as a mathematical branch in the service of other sciences (as demonstrated by the work of the mathematician Jacques-Louis Lions who explains: “What I like in applied mathematics, it is that they have the ambition to give the world of systems a representation that allows to understand and act “) would rather be without practical finality. On the contrary, mathematics has a large number of branches, at first abstract, having developed in contact with other disciplines such as statistics, game theory, combinatorial logic, information theory, theory graphs among other examples, as many branches that are not cataloged in applied mathematics but which nevertheless irrigate other scientific branches.
Nomothetic and idiographic sciences
A ranking of sciences can be based on the implemented methods. A first distinction of this order can be made between the nomothetic sciences and the idiographic sciences:
- the nomothetic sciences seek to establish general laws for phenomena likely to recur. It includes physics and biology, but also humanities or social sciences such as economics, psychology or even sociology.
- the idiographic sciences, on the contrary, deal with the singular, the unique, the non-recurrent. The example of history shows that it is not absurd to consider that the singular can be amenable to a scientific approach.
Wilhelm Windelband, a nineteenth-century German philosopher, is the author of the first draft of this distinction, Windelband’s reflection on the nature of the social sciences. In his History and Natural Science (1894), he argues that the opposition between the natural science and the science of the mind rests on a distinction of method and “forms of objectification”. Jean Piaget will use the term “nomothetic” to refer to disciplines seeking to derive laws or quantitative relations using strict or systematic experimentation methods. He cites scientific psychology, sociology, linguistics, economics and demography. He distinguishes these disciplines from historical, legal and philosophical sciences.
Empirical and logico-formal sciences
A categorization has been proposed by epistemology, distinguishing between “empirical sciences” and “logico-formal sciences“. Their common point remains mathematics and their use in related disciplines; however, in the words of Gilles-Gaston Granger, “the reality is not so simple. For, on the one hand, it is often on questions raised by empirical observation that mathematical concepts have been identified; on the other hand, if mathematics is not a science of nature, it has none the less true objects. According to Lena Soler, in her Introduction to Epistemology, she distinguishes, on the one hand, the formal sciences from the empirical sciences and, on the other, the sciences of the natures of the human and social sciences.
- the so-called empirical sciences concern the empirically accessible, sensitive world (accessible by the senses, therefore). They include: the natural sciences, whose object is to study natural phenomena; the human sciences, whose object is to study Man and his individual and collective behavior, past and present;
- on the other hand, the logico-formal sciences (or formal sciences) explore by deduction, according to rules of formation and demonstration, axiomatic systems. This is for example mathematics or logics
Natural sciences and social sciences
According to Gilles-Gaston Granger, there is another kind of epistemological opposition, distinguishing on the one hand the natural sciences, which have objects emanating from the sensible world, measurable and classifiable; on the other hand the sciences of man, also called human sciences, for which the object is abstract. Gilles-Gaston Granger also refuses to make from the study of the human phenomenon a proper science.
- the social sciences are those whose object is to study social phenomena; societies, their history, cultures, achievements and behaviors,
- the natural sciences are concerned with the natural world, the Earth and the Universe.
Common sense associates a discipline with an object. For example, sociology deals with society, the psychology with thought, physics deals with mechanical and thermal phenomena, and chemistry deals with the reactions of matter. Modern research nevertheless shows the absence of frontiers and the need to develop transversalities; for example, for certain disciplines we speak of “physicochemical” or “chemo-biological”, expressions that show the strong links between specialties. A discipline is ultimately defined by all the repositories it uses to study a set of objects, which forms its scientificity. Nevertheless, this criterion is not absolute.
For the sociologist Raymond Boudon, there is no single scientific and transdisciplinary. It is thus based on the notion of “family resemblance“, a notion already theorized by the philosopher Ludwig Wittgenstein according to which there are only formal similarities between the sciences, without, however, deriving a general rule making it possible to say what is “science”. Raymond Boudon, in The art of being persuaded of dubious, fragile or false ideas, explains that relativism “if it is a well-received idea […], is based on fragile foundations” and that, contrary to what Feyerabend preaches , “there is no reason to dismiss reason.”