Epistemology, from empiricism to logical positivism

Empiricism

(Isaac Newton)

Empiricism postulates that all knowledge comes essentially from experience. Represented by the English philosophers Roger Bacon, John Locke and George Berkeley, this current postulates that knowledge is based on the accumulation of observations and measurable facts, from which we can extract laws by an inductive reasoning (also said synthetic), therefore going from the concrete to the abstract. Induction consists, according to Hume, in the generalization of data of pure experience, called “empiric” (set of data of experience), which is thus the object on which the method bears. Nevertheless, Bertrand Russell mentions in his book Religion and Science what he calls the “scandal of induction”, this method of reasoning is not universal, indeed, according to him the laws admitted as general by the induction have only been verified for a number of experimental cases. In empiricism, reasoning is secondary whereas observation is first. Isaac Newton’s work testifies to an empirical method in the formalization of the gravitational law.

Empiricism breaks down itself into sub-currents:

the materialism that explains that only sensible experience exists;
the sensualism which considers that the knowledge comes from the sensations (it is the position of Condillac for example);
instrumentalism, which sees in theory an abstract tool that does not reflect reality.

Finally, empiricism would have made its way into the scientific field, according to Robert King Merton (in Elements of Theory and Sociological Method, 1965), thanks to his close links with Protestant and Puritan ethics. The development of the Royal Society of London, founded in 1660 by Protestants, is thus the perfect expression of it: “the combination of rationality and empiricism, so evident in Puritan ethics, forms the essence of the modern science, “says Merton.

Beyond empiricism and rationalism

With the ambition to refound science, and even more to reaffirm the scientific spirit, in a historical context dominated by doctrines and theories, Francis Bacon proposed to overcome the pitfalls of empiricism and rationalism: “Those who have treated of the sciences have been either empirics or dogmatical. The former like ants only heap up and use their store, the latter like spiders spin out their own webs. The bee, a mean between both, extracts matter from the flowers of the garden and the field, but works and fashions it by its own efforts. The true labor of philosophy resembles hers, for it neither relies entirely or principally on the powers of the mind, nor yet lays up in the memory the matter afforded by the experiments of natural history and mechanics in its raw state, but changes and works it in the understanding. We have good reason,[77] therefore, to derive hope from a closer and purer alliance of these faculties (the experimental and rational) than has yet been attempted.” (Novum organum).

Analytical theory of scientific knowledge

The analytic theory of scientific knowledge is a philosophical discipline that has developed mostly in the English-speaking world.

The Germanic world, by the Anglo-Saxon contribution, took again the analytical results to join them in a globalizing theory. The passage is very distinct from Locke, Berkeley, Hume to Kant for analytics. Fichte operates the reversal with his “Doctrine of Science” thus imposing the departure of a conception which is not meant to be only analytical but unifying. This will be much developed by Schelling and Hegel.

Kantian epistemology: criticism

For Roger Verneaux, who studied Kant’s thought, epistemology is, in the highest degree, and above all, “the critique of knowledge”. It is the noblest human enterprise as a prerequisite for any scientific endeavor.

Kant offers a radical change of perspective vis-à-vis of empiricism: it is a true epistemological revolution, which he describes himself by the famous expression of “Copernican revolution”. Hume had already placed the subject at the center of knowledge. Kant goes so far as to assert that the true origin of knowledge is in the subject and not in a reality with respect to which we would be passive.

He takes up some empiricist principles: “Thus, in time, no knowledge precedes the experience, and all begin with it,” he explains in Critique of Pure Reason.

For Kant, notes Claude Mouchot, “the object in itself, noumenon, is and will remain unknown” and “we will never know that phenomena”, and in this Kant remains very current. In the words of Kant (Critique of Pure Reason) “there are only the objects of the senses that can be given to us […] they can only be given in the context of a possible experience”.

Actually, Kant also remains so by his “recognition of the existence of (spatio-temporal) frames, through which reality is presented to us” Claude Mouchot still writes. However, the a priori character of these frames of classical mechanics (only existing at the time of Kant) can no longer be accepted today, following in particular the questioning of the notion of space-time by mechanics relativistic. At the very least we can consider these frameworks as constructed by the subject, which is the point of view of constructivism.

The positivist turn and the logical positivism

(Auguste Comte)

Auguste Comte distinguishes three historical states:

in the theological state, the mind of man seeks to explain natural phenomena by supernatural agents.
in the metaphysical state, the explanation is based on natural forces but still personified (the theory of the ether for example).
with the positive state, the mind no longer seeks to explain phenomena by their causes, but it is built on facts that are ascertainable and measurable.

The character of Newton is, for Comte, revealing of this “progressive march of the human spirit”.

Science must thus implement hypotheses, which make it possible to dispense with experience and lead to the formation of non-contradictory laws. Comte thus cites, as an example, Joseph Fourier’s theory of heat, which he built without having to observe the nature of the phenomenon. Positivism highlights the predictive quality of science, which allows to “see to predict” in the words of Comte, in his Discourses on the whole positivism (1843). Nevertheless, for him, the scientific method culminates in the putting into practice, in the action: what the modern discourse will call the scientific application. Engineering is thus the hand of science, characterized by know-how. Science is with Count inseparable from the action: