Physical Idealism

An idealistic trend of thought that emerged in the development of physics in the late 19th and early 20th centuries. In the development of physics, it was mainly the traditional spontaneous materialism that dominated. When idealism was associated with physics, Lenin called it a “term, which sounds very strange". This idealist trend of thought emerged because, in the face of the rapid development of physics, a few physicists, who did not have knowledge of materialist dialectics, could not correctly understand and interpret the major new achievements in physics. Influenced by metaphysical thinking methods, they exaggerated and rigidified certain concepts, elements and processes of cognition, made idealistic conclusions from them, and fell into idealism, thus forming the school of physical idealism.

Its representatives include Mach from Austria, Poincaré from France, Duhem from Belgium and Pearson from Britain.

After the discovery of electrons and radioactivesubstances, for example, it was proved that atoms can also be subdivided. This is usually supposed to show that human knowledge has penetrated from the atom to the inside of it. However, some physicists interpreted the disappearance of the boundary of understanding the structure of matter as "the disappearance of matter", and concluded from it that the objective existence of matter is disproved and thus fell into idealism. Another example is that some distorted the new achievements of physics by spliting the matter and the motion; then, they only began to talk about the motion by excluding the matter; finally, they completely attributed or reduced the motion to the sensory motion or the psychological thing, consequently, they reached the same idealist conclusion which denied the objective existence of the matter. The "model of the physical universe" of Pearson from Britain and the "energetics" of Ostwald from Germany belong to this type. Taking the continuous deepening of the process of understanding the development of physics and the continuous expansion of the scope of knowledge as an example, when certain new phenomena, new facts and new laws are found that can no longer be completely introduced into the framework of old concepts and old theories, the old concepts and old theories must be modified, enriched and supplemented. This process of the development of knowledge is supposed to be a dialectical development process from relative truth to absolute truth. However, some physicists interpreted this process as the "overthrow" of the old principles and the "crisis" in the development of physics, and thus, they suspected that physics theories are not objective truths and that physics is not the knowledge of objective reality. Therefore, they concluded that it is not nature that gives us the concepts of space and time, but we give them to nature; "everything that is not thought" is pure "nothing", and other idealist conclusions. Poincaré's "crisis of modern physics" is a typical example here. It can be seen that the roots of this idealist trend in physics mainly lies in the irredeemable errors in epistemology that they made.

Lenin compared this idealist trend in physics with physiological idealism that arose in the mid-19th century, which he analyzed and criticized. He pointed out that the epistemological errors made by physical idealism are mainly rooted in two aspects: one is the problem of so-called "mathematization" in the development of physics; the other is the problem of the dialectical development of the knowledge process from relative truth to absolute truth in the development of physics. Both problems were related to the characteristics of the development of physics in the late 19th and early 20th centuries.

On the problem of "mathematization". Engels, in his Dialectics of Nature, essentially referred to mathematics as "dialectical aids and expressions." Due to the dialectical character of nature itself, it is completely understandable to apply mathematical methods widely to natural sciences, especially to physics. Newton, for example, was characterized by his systematization and mathematization of the works of his predecessors, especially of Descartes, Kepler, Galileo, Huygens, and others. A proof of this is Newton's magnum opus The Mathematical Principles of Natural Philosophy published in 1687, where he said: “and the moderns, laying aside substantial forms and occult qualities, have endeavoured to subject the phenomena of nature to the laws of mathematics, I have in this treatise cultivated mathematics so far as it regards philosophy.” After Newton, Maxwell, who first theoretically discovered electromagnetic waves by using mathematical methods, was also characterized by systematization and mathematization of the work of his predecessors, especially of those since Faraday. Maxwell said: “My major task in this work is to convert Faraday’s physical ideas into mathematical form.” In this regard, Von Laue said in his History of Physics: “Just as a period of mathematical development of mechanics followed Newton, a similar era of mathematical elaboration of the Maxwellian theory now set in.” The works of Hertz, Poynting, Lorentz and Lamb after Maxwell is the proof of this. The birth of quantum and relativity theory at the beginning of the 20th century is even a greater proof. This is why people often use the terms "theoretical physics" and "mathematical physics" as the reciprocal terms. For example, what Poincaré calls "the present crisis of mathematical physics" in his book The Value of Science is essentially "the crisis of modern physics". It is under such historical conditions that some physicists, without the guidance of a correct philosophy, had "forgotten" the "matter", and crying as "the matter has disappeared" and "only some equations are left". As a result, they fell into the mire of idealism and formed an idealist trend . That is why, Lenin listed "mathematization" as the first reason for physical idealism.

As physics was developing in the late19th and early 20th centuries, the characteristics of the dialectical development process of knowledge from relative truth to absolute truth in the development of physics were more prominent than the time when Engels wrote Dialectics of Nature from 1873 to 1882. Due to the development of practice and the deepening of knowledge, especially the discovery of electrons and radioactive substances, some of what had been considered as absolute and unchangeable in the past have then proved to be relative and changeable. For example, the concept of "atom" had always been considered to be the absolute and indivisible ultimate particle of matter. But then it turns out that "atoms" are also variable and can be subdivided. For another example, the concept of "energy" had always been consideredas a complete continuum in the past. But since the discovery of quantum theory, it is clear that energy can also have a discontinuous aspect. Then take the most common concept, the "mass", which had always been considered to be constant and completely unrelated to the state of motion of an object. It has been proved by "special relativity" that the mass is also variable and closely related to its state of motion.

All these new discoveries show that knowledge is undergoing a dialectical development from relative truth to absolute truth. In the presence of such drastic developments in physics, physicists should have raised the traditional spontaneous metaphysical-mechanical materialism of the past in physics to the level of dialectical materialism represented by Marx. However, due to the limitations of social conditions, bourgeois physicists were unable to do so. On the contrary, especially because they did not understand dialectics and thereby could not properly understand and explain these significant new achievements in physics, they gave materialist explanations by using metaphysical thinking methods. Furthermore, some of them then fell from relativism to idealism. The so-called "the crisis of modern physics" of Poincaré is a typical example here. It refers to the whole physics, the whole natural science. Lenin pointed out that “It is mainly because the physicists did not know dialectics that the new physics strayed into idealism. They combated metaphysical (in Engels’, and not the positivist, i.e., Humean, sense of the word) materialism and its one-sided “mechanism”, and in so doing threw out the baby with the bath-water. Denying the immutability of the elements and of the properties of matter known hitherto, they ended by denying matter, i.e., the objective reality of the physical world. Therefore, Lenin listed the fall into idealism through "relativism" as another reason for the emergence of idealism in physics.

However, the new school of physical idealism was only a school with few proponents. As Lenin said, this “is a temporary deflection, a transitory period of sickness in the history of science, an ailment of growth, mainly brought on by the abrupt breakdown of old established concepts.“ Nevertheless, some philosophical idealists, especially the most reactionary believers and revisionists of all kinds in society, try their best to use it as if it were a lifeline to attack materialism. The result is the same as Lange, who tried to use physiological idealism to oppose materialism, without either refuting materialism or confirming idealism.