Science is both the statement of hypotheses concerning the nature of the world, and the verification of these theories as adequate to reality according to an experimental method, which differs according to the fields.
What are the origin and the nature of the structures that the subject must solicit to describe the object with which he is confronted?
|The structures may belong||Theory|
|to the subject||idealism|
|to the object||empiricism|
|to the subject and to the object||constructivism|
|exclusively to the relationship between subject and object||structuralism|
|neither to the subject nor to the object||platonic idealism|
Rationalism posits as a principle the dependence of scientific rules established by reason, mainly mathematical, physical, chemical rules, possibly supported by experimental verifications.
The founder of rationalism is most often considered to be René Descartes, who in the Discours de la méthode (1637) expounded his conception of the scientific method, and developed, in the Principes de la philosophie (1644), his view of the philosophy of science. The proposed method is very personal and deductive, the classification of sciences relates to the situation of the 17th century. The conditions in which Descartes elaborated his system are no longer exactly those of our time.
In a more radical conception, Auguste Comte founded positivism, thinking that the world could be reduced to phenomena explainable by “laws” expressed in mathematical language. This position has been discredited by epistemological criticism. It is often criticized for her subjective bias.
Empiricism posits the principle of dependence on evidence. It is one of the pillars of the philosophy of science, which has developed above all in the Anglo-Saxon world. Empiricism states that knowledge derives directly from human experience of the world, so the scientific statement comes and remains dependent on our experiences and observations. Scientific theories are constructed and tested through experimentation, methodical manipulation of experience, using empirical methods. This information drawn from experience, once gathered in sufficient numbers, can become a consensual basis for the scientific community which posits its principles as evidence, and establishes that this evidence will serve as the basis of scientific explanation. All science is therefore an attachment to empirical experience, to the invariant law, which would amount to saying according to certain schools of thought that science is fundamentally a reflexive a priori belief.
Observation involves perception, which makes it a cognitive act, an action of thought also dependent on how we can construct a rational understanding of the world. If that understanding changes, so do our observations, at least in appearance.
Scientists try to use induction, deduction, quasi-empirical methods, or even conceptual metaphors to transform this flow of observations into a self-consistent system.
Scientific realism and instrumentalism
Scientific realism, or naïve empiricism, consists of taking scientific discourse as the reality of the world. The term naive is not pejorative, but indicates that it is a question of sticking to scientific discourse to apprehend reality – which is the point of view of many scientists. Thus, a follower of realism will hold electrons and magnetic fields to exist.
Unlike realism, instrumentalism posits that our perceptions, scientific ideas and theories do not necessarily reflect the perfect reality of the world, but are useful means to explain, predict and control our experiences. From an instrumentalist’s point of view, electrons and magnetic fields are convenient ideas whose existence is contingent. Instrumentalism comes partly from pragmatism according to John Dewey.
In fact this current analyzes that science uses “explanatory hypotheses”, in other words the theories which have made it possible “until now” to predict observations.
Let’s take an example :
|When we drop an object, our experience tells us that it falls in a certain direction.A first theory could postulate (contrary to that in force today) that a force attracts the objects without variation as for their size and always in the direction given by our first test.
As long as the experiments apply only to objects of identical mass and in a reduced space (a garden for example) which does not suggest that the direction changes according to the masses of the surrounding objects, it is possible to use with success this first explanatory hypothesis, however false.
In the field of epistemology, constructivisms are currents of thought based on the idea that our representations, our knowledge, or the categories structuring this knowledge and these representations are the product of human understanding. Constructivism joins in its approach instrumentalism and pragmatism.
In sociology, social constructivism is at the crossroads of different currents of thought and was presented by Peter L. Berger and Thomas Luckmann in their book The Social Construction of Reality (1966). It seeks to discover how social reality and social phenomena are “constructed” i.e. how these phenomena are created, institutionalized and transformed into traditions.
Analysis and reductionism
Analysis is the breaking down of an observation or theory into simpler steps or concepts, in order to understand it. Analysis is essential to science, as it is to any rational enterprise. For example, it would be impossible to mathematically describe the movement of a projectile without separating the force of gravity, the angle of projection and the initial speed of the body set in motion. Only the separate analysis of these components, then their regrouping in a system, makes it possible to formulate a theory of the practical movement.
Reductionism in science can have different meanings. One type of scientific reductionism is the belief that all fields of study can ultimately be reduced to purely scientific explanation. Thus, a historical event can certainly be explained in sociological or psychological terms; from the reductionist point of view, this explanation can be described without loss of meaning in terms of human physiology, which can itself be described as the result of chemical or physical processes, so that the historical event is reduced to an event of physical science. This would therefore imply that the historical event was nothing more than the fruit of a physical scheme, which denies the existence of independent spontaneous phenomena. Physicalism is the reduction of all phenomena to phenomena explainable by physical laws.
At the simplest and shortest reductionism, by the suffix “ism” which designates a doctrine, consists in reducing the “complex” to the simple, like a two-dimensional photograph of a three-dimensional statue, biological complexity to mechanical simplicity. Reductionism is not Occam’s razor rule of explanatory economics.
“[…] Reductionism: To account for known data, any scholar must provide the simplest possible, most economical, and (usually) most elegant explanation possible. But reductionism becomes a flaw if one attaches excessive importance to the principle that the simplest explanation is the only one possible. Sometimes we have to consider the data in a larger Gestalt”. (Gregory Bateson, p. 235, Nature and Thought, Seuil, Paris, 1984).
Daniel Dennett showed that total reductionism was possible, while pointing out that it would be “bad science”, seeking to demonstrate too much from too little. The arguments put forward against such a reductionism are based on the idea that self-referenced systems indeed contain more information that can be described by individual behaviors, or participants in that of a group, than other systems. Concrete examples are fractal organizations or self-evolving systems discovered in chemistry. But the analysis of such organizations is necessarily destructive of information, because the observer must first select a sample of the studied system, which may be partially representative of the coherent whole. Information theory can be used to calculate the magnitude of information loss; it is moreover one of the techniques applied in the theory of chaos.
Scientific realism and metaphysics of science
The metaphysics of science is the project of developing a coherent and complete vision of nature on the basis of scientific theories. Science is not built on a foundationalist base – an absolute point of view – but it is in perpetual constitution (the boat of Neurath).
The metaphysics of science, which belongs to analytical philosophy, no longer consists solely of the analysis of language but more broadly of a systematic and argumentative discourse aimed at understanding the world and the position that human beings occupy in it. Pursuing Plato and Aristotle, it develops general categories that seek to grasp the being of the empirical world (cf. Aristotle, Metaphysics, Book 4) from a powerful anchoring in the sciences.
This project is a form of scientific realism characterized by:
- a metaphysical proposition: The existence and construction of nature are independent (ontology and causation) of scientific theories.
- a semantic proposition: The constitution of nature says which scientific theories are reliable (preferred term to “true” because science is in perpetual construction) and therefore which are not true (here the term is opportune).
- an epistemic proposition: The sciences are, in principle, capable of giving cognitive access to the constitution of nature. There are two discussions: one relating to the underdetermination of theory by experience (Pierre Duhem, 1906, Willard Van Orman Quine, 1951). The other relates to the cognitive leaps linked to the great advances that have been observed in the history of science (20th century).
This metaphysics of science project has at its disposal the universal and fundamental theories acquired since Newton, some of which are deterministic and others probabilistic (privileged position of physics). Special science theories are not universal and depend on fundamental physics theory. Unlike the theory of fundamental physics for which a principle of causal, nomological and explanatory completeness applies, the theories of special sciences are not complete.
Four metaphysical positions are possible related to 2 distinctions (David Lewis):
- Intrinsic properties (atomism) or relationships in a structure (holism).
- Categorical properties (purely qualitative) or causal properties (generating by their very nature certain effects)
Two other distinctions were also considered: properties as universals and properties as modes.
After having examined the distinctions, the special sciences such as quantum mechanics and biology in particular, as well as the philosophical currents of science such as scientific realism, Michael Esfeld concludes by taking care to recall the vassalage of philosophy on the state of knowledge of the science in the making and advises the avoidance of dynamics which lead to very dubious ontological commitments (such as the one postulating the existence of an infinity of parallel branches of the universe) [and which prevents] from achieving to a coherent vision of fundamental physics and the special sciences.
(Includes texts from Wikipedia translated and adapted by Nicolae Sfetcu)