Positivism and Logical Empiricism in the 19th century

The term positivism it derivates from August Comte. For his critical work, however, one can consider Hume as the first great positivist. He highlighted the impossibility of deductive reasoning producing assertions of fact, since deduction takes place and affects a second level, that of concepts.

Positivism and Logical Empiricism

The development of the term positivism It has, however, been incessant. The basic affirmations of positivism are:

1) That all factual knowledge is based on "positive" data from experience. -that reality exists, the contrary belief is called solipsism-.

2) That beyond the realm of facts there is logic and pure mathematics, recognized by Scottish empiricism and especially by Hume as belonging to "the relation of ideas."

In a later stage of positivism the sciences thus defined acquire a purely formal character.

Mach (1838-1916)

He claims that all factual knowledge consists of the conceptual organization and data processing of immediate experience. Theories and theoretical conceptions are only instruments of prediction.

In addition, theories can change, while observational facts maintain regularities. empirical and constitute firm (immutable) ground for scientific reasoning to be able to be grounded. Positivist philosophers radicalized empiricist anti-intellectualism, maintaining a radical utilitarian view of theories.

Avenarius (1843-1896)

He developed a biologically oriented theory of knowledge that influenced much of American pragmatism. Just as adaptation needs develop organs in organisms -Lamarckism-, thus knowledge develops theories for the prediction of future conditions.

The concept of cause is explained based on the regularity observed in the succession of events, or as a functional dependence between the observable variables. Causal relationships are not logically necessary, they are only contingent and determined by observation and especially by experimentation and inductive generalization -Hume-.

Many scientists of the 20th century, following the path opened by Mach, to which was added the influence of some "philosophers of mathematics" such as Whithead, Russell, Wittgenstein, Frege, etc., coalesced more or less unanimously around the positivist problem of the legitimacy of theories. scientific.

Russell states: "Either we know something regardless of experience, or science is a chimera."

Some philosophers of science, known as the group of Vienna Circle, established the principles of logical empiricism:

1. In the first place they believed that the logical structure of some sciences could be specified without taking into account their contents.

2. In second place established the principle of verifiability, according to which the meaning of a proposition must be established through experience and observation. In this way ethics, metaphysics, religion and aesthetics were left out of all scientific consideration.

3. In third place, proposed a unified doctrine of science, considering that there were no fundamental differences between physics and the biological sciences, or between the natural sciences and the social sciences. The Vienna Circle was at its peak during the period before the Second War.

Conventionalists

Another group of inductivists, of different orientation -among them those of influence Marxist, which is known as franckfurt school- are the Conventionalists, who argue that the main discoveries of science are, fundamentally, inventions of new and simpler systems of classification.

The fundamental features of classical conventionalism -Poincaré- are, therefore, decisiveness and simplicity. They are also, of course, anti-realists. In terms of Karl Popper (1959, pg. 79):

“The source of conventional philosophy seems to be awe at the austere and beautiful simplicity of the world as revealed in the laws of physics. The conventionalists (…) treat this simplicity as our own creation… (Nature is not simple), only the “laws of Nature” are; and these, the conventionalists maintain, are our creations and inventions, our arbitrary decisions and conventions ”.

Wittgenstein and Popper

This form of Logical Empiricism was soon opposed by other forms of thought: Wittgenstein, also a positivist, nevertheless confronts the verificationist positions of the Vienna Circle.

Wittgenstein argues that verification is useless. What language can communicate it "shows" is an image of the world. For the logical positivism heir to Wittgenstein, the logical formulas say nothing about the meanings of the propositions, but merely show the connection between the meanings of the propositions.

The fundamental answer will come from the falsificationist theory of Popper, which supports the impossibility of an inductive probability with the following argument:

"In a universe that contains an infinite number of distinguishable things or space-time regions, the probability of any universal law (not tautological) will be equal to zero." This means that as the content of a statement increases, its probability decreases, and vice versa. (+ content = - probability).

To solve this dilemma he proposes that one should try to falsify the theory, seeking the demonstration of the refutation or the counterexample. In addition, it proposes a purely deductivist methodology, actually negative hypothetical-deductive or falsificationist.

As a reaction to this approach, a series of theorists emerge who criticize logical positivism -Kuhn, Toulmin, Lakatos and even Feyerabend-, although they differ about the nature of the rationality exhibited by the change scientific. They defend notions such as scientific revolution, as opposed to progress -Kuhn-, or the intervention of irrational processes in science -Feyerabend's anarchist approach-.

Popper's heirs now gather under the Critical Rationalism, in a last effort to save science, theory and the notion of "scientific progress", which they do not without a certain difficulty, proposing as alternatives, among others, the establishment of rival Research Programs, defined for his heuristic, and compete with each other.

The difficulties of logic models applied to the methodology of Science, therefore, could be summarized as follows:

The induction of the theory, from particular data, was already clearly not justified. A deductivist theory will accomplish nothing because there are no sure general principles from which deduction can be derived. A falsificationist vision is inadequate because it does not reflect scientific practice - scientists do not operate that way, abandoning theories when they present anomalies.

The result appears to be a skepticism generalized in terms of the possibility of distinguishing between valid theories and ad hoc theories, which is why it usually ends up appealing to history, it is that is, over time as the only safe method, or at least with certain guarantees, to judge the adequacy of the models - another form of conventionalism-.