Max Born (1949), Natural Philosophy of Cause and Chance

Max Born (1949), Natural Philosophy of Cause and Chance
From “Metaphysical Conclusions”, pp. 124-28
[My emphasis added in bold]

“[T]he principle of objectivity…provides a criterion to distinguish subjective impressions and objective facts, namely by substituting for given sense-data others which can be checked by other individuals. […] It is perhaps the most important rule of the code of natural science of which innumerable examples can be given, and it is obviously closely related to the conception of scientific reality. For if reality is understood to mean the sum of observational invariants – and I cannot see any other reasonable interpretation of this word in physics – the elimination of sense qualities is a necessary step to discover them.

“Here I must refer to the previous Waynflete Lectures given by Professor E.D. Adrian, on The Physical Background of Perception, because the results of physiological investigations seem to me in perfect agreement with my suggestion about the meaning of reality in physics. The messages which the brain receives have not the least similarity with the stimuli. They consist in pulses of given intensities and frequencies, characteristic for the transmitting nerve-fibre, which ends at a definite place of the cortex. All the brain ‘learns’ (I use here the objectionable language of the ‘disquieting figure of a little hobgoblin sitting up aloft in the cerebral hemisphere’) is a distribution or ‘map’ of pulses. From this information it produces the image of the world by a process which can metaphorically be called a consummate piece of combinatorial mathematics: it sorts out of the maze of indifferent and varying signals invariant shapes and relations which form the world of ordinary experience.

“This unconscious process breaks down for scientific ultra-experience, obtained by magnifying instruments. But then it is continued in the full light of consciousness, by mathematical resoning. The result is the reality offered by theoretical physics.

“The principle of objectivity can, I think, be applied to every human experience, but is often quite out of place. For instance: what is a fugue by Bach? is it the invariant cross-section, or the common content of all printed or written copies, gramophone records, sound waves at performances, etc., of this piece of music? As a lover of music I say No! that is not what I mean by a fugue. It is something of another sphere where other notions apply, and the essence of it is not ‘notions’ at all, but the immediate impact on my soul of its beauty and greatness.

“In cases like this, the idea of scientific objective reality is obviously inadequate, almost absurd.

“This is trivial, but I have to refer to it if I have to make good my promise to discuss the bearing of modern physical thought on philosophical problems, in particular on the problem of free will. Since ancient times philosophers have been worried how free will can be reconciled with causality, and after the tremendous success of Newton’s deterministic theory of nature, this problem seemed to be still more acute. Therefore, the advent of indeterministic quantum theory was welcomed as opening a possibility for the autonomy of the mind without a class with the laws of nature. Free will is primarily a subjective phenomenon, the interpretation of a sensation we experience, similar to a sense impression. We can and do, of course, project it into the minds of our fellow beings just as we do in the case of music. We can also correlate it with other phenomena in order to transform it into an objective relation, as the moralists, sociologists, lawyers do – but then it resembles the original sensation no more than an intensity curve in a spectral diagram resembles a colour I see. After this transformation into a sociological concept, free will is a symbolic expression to describe the fact that the actions and reactions of human beings are conditioned by their internal mental structures and depend on their whole and unaccountable history. Whether we believe theoretically in strict determinism or not, we can make no use of this theory since a human being is too complicated, and we have to be content with a working hypothesis like that of spontaneity of decision and responsibility of action. If you feel that this clashes with determinism, you have now at your disposal the modern indeterministic philosophy of nature, you can assume a certain ‘freedom’, i.e., deviation from the deterministic laws, because these are only apparent and refer to advantages. Yet if you believe in perfect freedom you will get into difficulties again, because you cannot neglect the laws of statistics which are laws of nature.

“I think that the philosophical treatment of the problem of free will suffers often from an insufficient distinction between the subjective and objective aspect. It is doubtless more difficult to keep these apart in the case of such sensations as free will, than in the case of colours, sounds, or temperatures. But the application of scientific conceptions to a subjective experience is an inadequate procedure in all such cases.

“You may call this an evasion of the problem, by means of dividing all experience into two categories, instead of trying to form one all-embracing picture of the world. This division is indeed what I suggest and consider to be unavoidable. If quantum theory has any philosophical importance at all, it lies in the fact that it demonstrates for a single, sharply defined science the necessity of dual aspects of complementary considerations. Niels Bohr has discussed this question with respect to many applications in physiology, psychology, and philosophy in general. According to the rule of indeterminacy, you cannot measure simultaneously position and velocity of particles, but you have to make your choice. The situation is similar if you wish, for instance, to determine the physico-chemical processes in the brain connected with a mental process: it cannot be done because the latter would be decidedly disturbed by the physical investigation. Complete knowledge f the physical situation is only obtainable by a dissection which would mean the death of the living organ or the whole creature, the destruction of the mental situation. This example may suffice; you can find more and subtler ones in Bohr’s writings. They illustrate the limits of human understanding and direct the attention to the question of fixing the boundary line, as physics has done in a narrow field by discovering the quantum constant ℏ. Much futile controversy could be avoided in this way. To show this by a final example, I wish to refer to these lectures themselves which deal only with one aspect of science, the theoretical one There is a powerful school of eminent scientists who consider such things to be a future and snobbish sport, and the people who spend their time on it drones Science has undoubtedly two aspects: it can be regarded from the social standpoint as a practical collective endeavor for the improvement of human conditions, but it can also be regarded from the individualistic standpoint, as a pursuit of mental desires, the hunger for knowledge and understanding, a sister of art, philosophy, and religion. Both aspects are justified, necessary, and complementary. The collective enterprise of practical science consists in the end of individuals and cannot thrive without their devotion. But devotion does not suffice; nothing great can be achieved without the elementary curiosity of the philosopher. A proper balance is needed. I have chosen the way which seemed to me to harmonize best with the spirit of this ancient place of learning.”