philosopher who has properly grasped it is unable to conceive the negative. A few extracts will suffice to show the remarkable importance which he attaches to this law:—
"All the particular advances of physics and chemistry yield in theoretical importance to the discovery of the great law which brings them to one common focus, the 'law of substance.' As this fundamental cosmic law establishes the eternal persistence of matter and force, their unvarying constancy throughout the entire universe, it has become the pole-star that guides our monistic philosophy through the mighty labyrinth to a solution of the world-problem" (p. 2).
"The uneducated member of a civilised community is surrounded with countless enigmas at every step, just as truly as the savage. Their number, however, decreases with every stride of civilisation and of science; and the monistic philosophy is ultimately confronted with but one simple and comprehensive enigma—the 'problem of substance'" (p. 6).
"The supreme and all-pervading law of nature, the true and only cosmological law, is, in my opinion, the law of substance; its discovery and establishment is the greatest intellectual triumph of the nineteenth century, in the sense that all other known laws of nature are subordinate to it. Under the name of 'law of substance' we embrace two supreme laws of different origin and age—the older is the chemical law of the 'conservation of matter,' and the younger is the physical law of the 'conservation of energy.' It will be self-evident to many readers, and it is acknowledged by most of the scientific men of the day, that these two great laws are essentially inseparable" (p. 75).
"The conviction that these two great cosmic theorems, the chemical law of the persistence of matter and the physical law of the persistence of force, are fundamentally one, is of the utmost importance in our monistic system. The two theories are just as intimately united as their objects—matter and force or energy. Indeed, this fundamental unity of the two laws is self-evident to many monistic scientists and philosophers, since they merely relate to two different aspects of one and the same object, the cosmos" (p. 76).
"I proposed some time ago to call it the 'law of substance,' or the 'fundamental cosmic law'; it might also be called the 'universal law,' or the 'law of constancy,' or the 'axiom of the constancy of the universe.' In the ultimate analysis it is found to be a necessary consequence of the principle of causality" (p. 76).
I criticise these utterances below, and I also quote extracts bearing on the subject from Professor Huxley in Chapter IV.; but meanwhile Professor Haeckel is as positive as any Positivist, and runs no risk of being accused of Solipsism:—
"Our only real and valuable knowledge is a knowledge of nature itself, and consists of presentations which correspond to external things." … "These presentations we call true, and we are convinced that their content corresponds to the knowable aspect of things. We know that these facts are not imaginary, but real" (p. 104).
He also tends to become sentimental about the ultimate reality as he perceives it, and tries to construct from it a kind of religion:—
"The astonishment with which we gaze upon the starry heavens and the microscopic life in a drop of water, the awe with which we trace the marvellous working of energy in the motion of matter, the reverence with which we grasp the universal dominance of the law of substance throughout the universe—all these are part of our emotional life, falling under the heading of 'natural religion'" (p. 122).
"Pantheism teaches that God and the world are one. The idea of God is identical with that of nature or substance. … In pantheism, God, as an intra-mundane being, is everywhere identical with nature itself, and is operative within the world as 'force' or 'energy.' The latter view alone is compatible with our supreme law—the law of substance. It follows necessarily that pantheism is the world-system of the modern scientist" (p. 102).
"This 'godless world-system' substantially agrees with the monism or pantheism of the modern scientist; it is only another expression for it, emphasising its negative aspect, the non-existence of any supernatural deity. In this sense Schopenhauer justly remarks:
"'Pantheism is only a polite form of atheism. The truth of pantheism lies in its destruction of the dualist antithesis of God and the world, in its recognition that the world exists in virtue of its own inherent forces. The maxim of the pantheist, 'God and the world are one,' is merely a polite way of giving the Lord God his congé'" (p. 103).
Thus we are led on, from what may be supposed to be a bare statement of two recent generalisations of science—first of all to regard them as almost axiomatic or self-evident; next, to consider that they solve the main problem of the universe; and, lastly, that they suffice to replace the Deity Himself.
To curb these extravagant pretensions it is only necessary to consider soberly what these physical laws really assert.
Conservation of Energy.
Take first the conservation of energy. This generalisation asserts that in every complete material system, subject to any kind of internal activity, the total energy of the system does not change, but is subject merely to transference and transformation, and can only be increased or diminished by passing fresh energy in or out through the walls of the system. So far from this being self-evident, it required very careful measurement and experimental proof to demonstrate the fact, for in common experience the energy of a system left to itself continually to all appearance diminishes; yet it has been skilfully proved that when the heat and every other kind of product is collected and measured, the result can be so expressed as to show a total constancy, appertaining to a certain specially devised function called "energy," provided we know and are able to account for every form into which the said energy can be transformed by the activity going on. A very important generalisation truly, and one which has so seized hold of the mind of the physicist that if in any actual example a disappearance or a generation of energy were found, he would at once conclude either that he had overlooked some known form and thereby committed an error, or that some unknown form was present which he had not allowed for: thereby getting a clue which, if followed up, he would hope might result in a discovery.
But the term "energy" itself, as used in definite sense by the physicist, rather involves a modern idea and is itself a generalisation. Things as distinct from each other as light, heat, sound, rotation, vibration, elastic strain, gravitative separation, electric currents, and chemical affinity, have all to be generalised under the same heading, in order to make the law true. Until "heat" was included in the list of energies, the statement could not be made; and, a short time ago, it was sometimes discussed whether "life" should or should not be included in the category of energy. I should give the answer decidedly No, but some might be inclined to say Yes; and this is sufficient as an example to show that the categories of energy are not necessarily exhausted; that new forms may be discovered; and that if new forms exist, until they are discovered, the law of conservation of energy as now stated may in some cases be strictly untrue; just as it would be untrue, though partially and usefully true, in the theory of machines, if heat were unknown or ignored. To jump, therefore, from a generalisation such as this, and to say, as Professor Haeckel does on page 5, that the following cosmological theorems have already been "amply demonstrated," is to leap across a considerable chasm:—
"1. The universe, or the cosmos, is eternal, infinite, and illimitable.
"2. Its substance, with its two attributes (matter and energy), fills infinite space, and is in eternal motion.
"3. This motion runs on through infinite time as an unbroken development, with a periodic change from life to death, from evolution to devolution.
"4. The innumerable bodies which are scattered about the space-filling ether all obey the same 'law of substance'; while the rotating masses slowly move towards their destruction and dissolution in one part of space, others are springing into new life and development in other quarters of the universe."
Most of this, though in itself probable enough, must, when scientifically regarded, be rated as guess-work, being an overpressing of known fact into an exaggerated and over-comprehensive form of statement. Let it be understood that I am not objecting to his speculations, but only pointing out that they are speculations.
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