Excerpts from The Making of the Modern Mind (1926)
by John Herman Randall, Columbia University
Basic Generalizations Unifying the Fields of Physics and Chemistry
Three main movements are discernible in this nineteenth-century spread of mechanistic explanation: first, the unification of the field of physics and chemistry through certain fundamental generalizations; secondly, the introduction of mechanism into the realm of biology, of living beings; and thirdly, the application of the same viewpoint and method to the study of human nature itself. This is not the place to enter into any detailed consideration of the progress of scientific discovery and theory . . . But since it is beyond question the most important intellectual force in the last hundred years, it is worth while to present even a very inadequate summary of its significance. It was science, the mathematical-physical experimental learning of the seventeenth and eighteenth centuries, that really wrought the changes from the intellectual world of the Middle Ages . . . increasingly it has been the growth of scientific knowledge that has caused the steady spread of the naturalistic viewpoint in every field. . .
Those sciences, like physics and astronomy and chemistry, in which the Newtonian world had been rooted, witnessed a double movement: on the one hand, they became less confident of mathematical hypotheses unchecked by the most careful experimentation . . . on the other, this very mass of observations led men to the formulation and verification of sweeping generalizations stating in mathematical terms the fundamental relationships between physical phenomena. Physicists . . . carried their analysis further and further. In the kinetic theory of matter they worked out in detail a molecular mechanics that would draw together all the investigations of solids, fluids, and gases, together with the phenomena of heat and sound, and explain all so-called physical properties of bodies in terms of the energy of motion of their component particles. The vast sciences of electricity and magnetism, mere idle curiosities in the previous century, opened up a new world of electro-magnetic energy following laws even more basic than those of mechanics; to explain these phenomena it became necessary to analyze even theatom into its further component parts, the electrons. Chemists, bringing order into their science by a verifiable atomic theory set in mathematical terms, discovered the Periodic Law of atomic weights, and found themselves led to the same analysis of the atom into electrons which had been necessary in physics. The two sciences merged in their roots into one . . . and it seems as though matter and motion together are dissolving into a common form of electronic energy, whose laws, when completely formulated, will be able to include all physical and chemical laws as special instances.
In the achievement of such a mathematical synthesis of all physical phenomena, three main stages may be distinguished. The first was the work of the seventeenth century; Galileo and Newton formulated the universal laws of motion and gravitation. The second sprang chiefly from the study of the steam engine and the other heat-producing machines of the early nineteenth century; it is expressed in the great generalization of the Conservation of Energy. This developed from the determination of the mechanical equivalent of heat, undertaken by Rumford and Davy; but the final enunciation is due mainly to Joule in England and Mayer and Helmholtz in Germany. The latter [Helmholtz] phrased it:
The last decades of scientific development have led us to the recognition of a new universal law of all natural phenomena, which, from its extraordinarily extended range, and from the connection which it constitutes between natural phenomena of all kinds, even of the remotest times and the most distant places, is especially fitted to give us an idea of the character of the natural sciences. This law is the Law of the Conservation of Force; it asserts, that the quantity of force which can be brought into action in the whole of Nature is unchangeable, and can neither be increased nor diminished.
This law is often called the First Law of Thermodynamics; the second law, formulated by Kelvin, is that of the Dissipation of Energy, that while the total energy in the universe is constant, the sum of useful energy is diminishing by its ultimate conversion into non-useful or dissipated heat . . . These great generalizations, it should be noted, like the earlier Newtonian principle of the universal scope of the laws of mechanics, while marvelously valuable in uniting the varied phenomena of nature under a few fundamentallaws, are assumptions rather than absolutely verified theories, assumptions necessary to science, but assumptions of the scientific faith none the less.
It still remained to bring the phenomena of light, electricity, and magnetism together, and to link them with the foundations of mechanics and of chemistry. As a result of the work of Thomas Young and [Augustin] Fresnel, it was definitely established that light is a form of wave-motion in some medium. Coulomb and Ampère in France, Ohm in Germany, and Faraday and Kelvin in England, discovered and formulated the laws of electro-statics, electro-magnetism, and of galvanic currents; and Faraday suggested, with brilliant intuition, though he did not work out the theory mathematically, that all these facts could be referred to the effects of motion in what he called an electro-magnetic field, and that this field possessed much in common with the medium, ether, which the wave theory of light made it necessary to assume.
Thus three great generalizations had been achieved by the middle of the century [i.e., 1850]: Newtonian mechanics, the atomic theory of chemistry, and the kinetic theory of matter, light, electricity, and magnetism.
None of these three principles, however, appeared sufficient to cover the whole field . . . The unification of scientific thought which was gained by any of these three views, was thus only partial. A more general term had to be found under which the different terms could be comprised, which would give a still higher generalization, a more complete unification of knowledge. [quoted from J. T. Merz, History of European Thought in the Nineteenth Century, II, ch. 6]
This conception was electro-magnetic energy, and its definition and formulation, begun by Clerk Maxwell, Helmholtz, and Hertz, lies at the foundation of all subsequent study of the electron and radio-activity, as well as the mathematical synthesis of the other three principles.
Clerk Maxwell set to work to study the energy of the electro-magnetic field by applying the law of the Conversation of Energy. Where Faraday had been content with mechanical analogy for his fruitful conception, Clerk Maxwell, a brilliant mathematician, reduced its properties to exact measurement. He succeeded in identifying completely all the various experimentally ascertained electric and magnetic phenomena, fixing their nature and quantities in conformity with experience, and arriving finally at the suggestion that the velocity of the transmission of electro-magnetic forces must be the same as that of light, the latter being but a special form of such disturbance. "We can scarcely avoid the inference that light consists in the transverse undulations of the same medium which is the cause of electric and magnetic phenomena" [quoted from James Clerk Maxwell]. Hertz verified Clerk Maxwell's calculations by detailed experiment, proving the fundamental character of the electro-magnetic field and its energy . . .
We seem to-day to be in the midst of a new revolution in physics, a revolution whose real significance will probably not be apparent for some time. The discovery that the laws of Newtonian mechanics are after all but special cases of more fundamental and more generalized mechanical principles, a discovery which the popular imagination associates with Einstein, one of the formulators of theprinciple of general relativity, seems but a single illustration of what is going on. The very foundations of physics are being scrutinized in the interests of making them more inclusive and all-embracing . . . What the outcome will be, no one can hazard; but no one doubts that it will mean a still further universalization of more and more comprehensive mechanistic explanations of everything in the world. We are still following in the path laid out by Newton. [pp. 460-465]
1) What are the main points made by the author in these excerpts?
2) What is the author's position on the importance of science? What generalizations does he make regarding the future development of science? Be specific.