ON THE LIMITS OF SCIENCE. BY WILLIAM FORSYTH, Q.C. M.P. From Fraser's Magazine. Iperiment. I think it is Herschel who somewhere says that if a man were confined from childhood in a prison, he might be able to reason out all the truths of THE present is an age distinguished pure mathematics, but he never could by the supremacy of science, and remark-tell, unless he saw it, what would become able for the discoveries she has made. of a lump of sugar when thrown into More has been done to unravel the mys-water. teries of nature during a few recent gen- In illustration of this I will take as an erations than was accomplished for more instance the rise of water in a pump. It than two thousand five hundred years was matter of common experience that before. And it is worth while to con- the suction of the piston was followed by sider the cause of this, for undoubtedly, the rise of water in the well. How was like everything else, there must be a it to be accounted for? The Greeks had cause for so marked and astonishing a sense enough to see that a vacuum was contrast. The Greek mind was singular-created above the water, and having ly acute and intelligent, and yet little or established in their minds a theory that no progress was made in physical science" Nature abhors a vacuum," they thought by the gifted philosophers of that nation. this a sufficient reason to explain the The Romans could conquer the world, occurrence. As nature abhorred a vacand yet they were ignorant of some of uum, she testified her abhorrence by the commonest principles of mechanics making the water fill it. Now, here there and hydrostatics and astronomy such as is obviously no physical cause given to are now familiar to intelligent school-account for the physical effect. It is boys. Why was this? They had the merely an imaginary reason utterly unsame means of observation that we have, supported by any mechanical proof.. but they mistook altogether the condi- And yet this theory, that nature abhors tions upon which alone scientific prog- a vacuum, was accepted as a suffiress can be made. To learn the secrets cient explanation of every phenomenon, of nature we must become her pupil. of a fluid, whether liquid or aëriform, "Natura enim non nisi parendo vincitur," rushing in to fill empty space, for more as Bacon said, and we can ascertain her than two thousand years. At last, in the hidden laws and processes only by act-middle of the seventeenth century, when ual experiment and severe induction. some engineers were employed by the But experiment must be conducted Duke of Tuscany to sink a well near under the influence of ideas proper to the Florence of an unusual depth, it was found subject-matter, or it will be barren and that the pump would not work. They unfruitful. It will not do merely to col- applied to Galileo, then an old man living lect individual facts unless we know how at Fiesole, to explain the reason, and he, to group and classify them, and unless half in jest and half in earnest, told them we can detect the significance of the that he supposed that nature did not abvarying results presented to our view, hor a vacuum above ten mètres. But Toreven although at the time we may not be ricelli, a pupil of Galileo, applied himself able to explain them. Above all we must to the problem, and he soon satisfied himbe unalterably convinced that every self that a column of water thirty-three physical effect has a physical cause, and feet high, which is the utmost height to that our proper business is by careful which water can be raised in a pump, observation and experiment to point out must be raised by some mechanical force what this cause is, so far as our limited equivalent to the weight of water sup. faculties will allow. But this was not ported. He made experiments, and the course pursued by the philosophers found that this mechanical force was of Greece. They thought that they nothing else than the weight of the atcould reason out the causes of the phe-mosphere. Here, then, was the discovnomena of nature from certain principles ery by scientific experiment of an unsuswhich they assumed without any proof to pected truth that the air has definite be part of her constitution, but which weight, and a weight exactly equal to that really existed only in their own minds. of a column of water thirty-three feet They reasoned in fact a priori, by which high. But men are slow to admit what process scientific truths in physics will shocks a long-cherished opinion or prejunever be discovered; for it presupposes dice, and it was not until Pascal demona knowledge of certain laws which can strated the truth of Torricelli's theory by only be known by observation and ex-'experimentally showing that mercury in 31 the barometer (invented by Torricelli) substance, he said that the sun's light We need not go through the dreary waste of the Middle Ages dreary, I mean, as regards scientific truths-for unless we make an exception in the case of Roger Bacon, it was not illuminated by a single ray of scientific discovery. Nor is this at all surprising. The tone and temper of that dark period were utterly unfit for the investigation of truth. The mind of Western Europe lay spellbound under the domination of one great name, and it was thought almost blasphemous to question the authority of Aristotle in any matter of physical science or moral philosophy. Ipse dixit was generally thought a conclusive answer to any curious enquiry, and it was expressly asserted that the whole of philosophy was contained in his logic. Instead, however, of the four elements, earth, fire, air, and water, which the ancients believed to be the primeval constituents of all things, the writers of the Middle Ages substituted salt, sulphur, and mercury, and, like the Greeks, and Romans, they assumed certain principles to explain phenomena - such as that fluids do not gravitate in proprio loco. Thus water does not gravitate on water because it is in its own place, and air has no gravity on water because it is above water, which is its proper place, and earth in water descends because its proper place is below water. So again with regard to astronomy. The Greeks were intelligent observers of the heavenly bodies, and they had amongst them able mathematicians, but instead of ascertaining by careful and accurate observation what the actual The distinguishing merit of Bacon curves were which the planets described, in the history of science was not that he they set out with a theory that as the himself made any actual discoveries, but circle is the most perfect of figures it that he was the first to emancipate the must necessarily follow that the planets human intellect from the thraldom of revolve in circles, and they framed a most Aristotle. He says in his "Advancement ingenious and complicated system of ec- of Learning," ""For as water will not ascentric circles and epicycles, which, in a cend higher than the level of the first sort of fashion, did account for the move-spring-head from whence it descendeth, ments of the celestial bodies. Thus also so knowledge derived from Aristotle, and when Aristotle tried to explain why, when the sun's light passed through a square hole, the bright image is round, instead of imitating the figure of the hole, as shadows resemble the figures of their exempted from liberty of examination, will not rise again higher than the knowledge of Aristotle." And again, "Antiquity deserveth that reverence, that men should make a stand thereupon and dis cover what is the best way; but when the discovery is well taken, then to make progression." But more than this- Bacon first insisted upon the true and only method by which the secrets of nature can be made known, namely, patient experiment and severe induction. with them as if they were the final and efficient causes of all the phenomena of nature. Link after link in the great chain of causation is unrolled under the searching analysis of the philosopher, until he is apt to forget that he can never get to the end of the chain, and he contents I need not occupy space by even glan- himself with the idea that it is self-supcing at the magnificent results which porting. In other words, he is in danger science has achieved since men began to of substituting the blind energy of matter follow the right track and patiently ex- and its inherent properties for an intelliplore the mysteries of nature by a care- gent First Cause, by whose almighty will ful attention to the conditions under that energy and those properties were which alone she will reveal a knowledge given. The consequence of this, if not of her laws. Of all the physical sciences corrected by other views, is first sceptichemistry seems to be the one in which cism, and then denial of a Creator. Rethe most wonderful discoveries have been ligion, of course, can have no place in made, and such as interest and fascinate such a theory indeed the word superus most. She can decompose the rocks natural can have no meaning where nawhich form the skeleton of the globe, and | ture is supposed to be self-sufficient to then, by fusing the constituents togeth- produce everything. This, then, is the er in different proportions, produce com- danger, and I will venture to suggest pounds which are the same as the quartz and lime and sand and clay which exist in such abundance in nature. She shows that all vegetable and animal life is sustained by combustion, which at first appears a paradox, but is nevertheless, strictly true. In animals the seat of combustion is the lungs the substance burnt is sugar, which consists of carbon, hydrogen, and oxygen and the products of the combustion are carbonic acid gas and aqueous vapour. some considerations which will show that such a result is not only unsupported by fact, but is, in the strictest sense of the word, unphilosophical. For philosophy does not imagine causes. She only investigates and verifies them. And the most exhaustive analysis which chemistry can apply to the composition of matter absolutely and entirely fails when we attempt to account for and explain its essential properties. Let me expand my meaning more fully. All the matter with which man is It is, however, unnecessary to speak of acquainted is composed of one or more of the progress and triumphs of science. elementary substances, such as calcium, No one is more willing than myself to do carbon, hydrogen, oxygen, nickel, phosher homage, and in her proper sphere she phorus, silicon, sulphur, sodium, merreigns unrivalled and supreme. Nor is cury, the ordinary metals, and the rest. the habit of mind which she requires in By elementary substances I mean those her votaries useful only in her peculiar which so far as we know at present candomain. We use the word science with not be decompounded, although very reference to other things than the mate- possibly we shall find at some future rial universe. Thus we speak of the time that some of them will yield to solscience of political economy, and meta- vents and prove to be compound bodies. physical science, and the science of juris- This, however, is quite immaterial to my prudence. When we dignify them by argument. This we know with absolute that name we mean that we can reason certainty, that they have the power of from certain principles and deduce cer- combining together in certain definite tain results in logical sequence from them. proportions by what is called chemical There is, in fact, in almost all subjects, affinity. Thus water consists of two pera scientific and an unscientific method of manent gases, oxygen and hydrogen, conenquiry, and it is impossible to exagger-densed by the force of chemical affinity ate the importance of adopting the former to a liquid condition. One cubic foot of in preference to the latter. But after water yields more than eighteen hundred having said all this, there are certain cubic feet of a mixture of these two gases, words of caution which seem to be pecul- and so great is their power to resist presiarly needed at the present time. The danger of too exclusive a devotion to physical science is that the mind is so occupied with secondary causes that it is tempted to rest upon and be satisfied' sure, that a weight of twenty tons to a square inch is not sufficient to reduce them to a liquid state. Let us consider what must be the force or forces in a little drop of water which are able to over come the mighty tendency of the gases Let us pause here. Are not ideas of to expand themselves into an aëriform symmetry and number inherent in the condition. They can be decomposed by human mind as purely intellectual conelectricity, but Faraday proved that it re- ceptions? And can we believe them to be quires more electricity to decompose a exhibited in nature by a mere concourse of drop of water than to charge a thunder- atoms, or by self-existing and self-created cloud. Now, I want to know if the ma- properties of matter without the interventerialist can tell me anything of the ori-tion of intelligence and mind? The natugin or nature of this prodigious power, ralist here is utterly at fault. He does not or, indeed, of the cause of chemical af- even attempt a solution. He arrives at finity at all. We can in imagination these ultimate results by observation and build up this world of ours out of the ele-experiment in a legitimate manner, and mentary substances I have mentioned; then he arbitrarily frames an hypothesis that is, we can show that all the moun- of which he has not a shadow of proof, tains and rocks and lands and seas are and asks us to assume that there are ulactually formed by certain combinations timately self-created forces or atoms or of them. Thus calcium combined with molecules, of which he confesses he oxygen produces lime, silicon combined knows nothing, which of themselves were with oxygen produces silica or quartz, able to evolve symmetry and order and aluminum combined with oxygen pro- numerical proportion, and, in fact, create duces alumina, and alumina combined the universe as we find it. Now this, I with silica produces clay, and so on. But say, is unphilosophical in the highest deno chemist can tell us why these bodies gree. It is little better than going back so combine, and why such and such a to the occult qualities of nature by which body is the result. But, more than this; the philosophers of antiquity sought to every solid body, when slowly deposited explain phenomena, whereas, in fact, they from a liquid or aëriform condition, as- explained nothing. sumes a definite symmetrical shape, The truth is, we know nothing of the which we call crystal, and the process by ultimate constituents and the cause of the which it is so formed we call crystalliza- formative power of matter. If we contion. Now, it is a most remarkable fact fine ourselves to matter alone, that will that all crystals, without exception, are tell us nothing about them, although we solids bounded by plane faces, symmetri- can by analysis and experiment discover cally disposed about certain straight lines the modes and processes and conditions: called axes. No mathematician could under which they work. We know that: determine the angles which the axes and what we call gravitation is a force by: planes in the different figures, by a con- which every particle of matter attracts. stant law, make with each other with every other particle and which varies in more accuracy than they are found to ex-versely as the square of the distance, just ist in nature. Moreover, we find numer- as we know that twenty-three parts of soical relations of the most remarkable dium will exactly unite with 35'5 of chlokind to exist in the proportions in which rine and produce common salt. But as alone natural substances will combine, to what gravitation really is, and as to the and these numerical relations exist also in plants when we ascend into the region of vegetable life. Nothing is more striking in botany than the mode in which certain numbers, such as three and five and their multiples, prevail. Plants which are monocotyledonous that is, have only one seed-leaf - have generally, if not always, three sepals in the calyx, and three petals or multiples of three on the corolla; while those which are dicotyledonous that is, have two seed-leaves-have for the most part five sepals, and five petals, and five stamens, or multiples of five. The same is true if four be what we may call the ruling number in any family of plants. The disposition of the leaves on the stem follows also a most curious numerical law. LIVING AGE, VOL. IX. 455 - reason why bodies will unite in only fixed and definite proportions, we are profoundly and helplessly ignorant. Take, again, botany. We can trace the growth of a plant from a minute cell into root, stem, leaf, and flower. We can see as a fact that the pollen of the anthers of the stamens must strike the stigma of the pistil, and be conveyed down the style: to the ovary in order that fecundation may be there produced, and the minute: cell. formed, which by the addition of other cells perpetually superadded, grows up into the perfect plant. But by virtue of what powers such a life-producing cell is. created-which by the absorption of moisture from the ground, and the agency of solar light and heat, is able to produce a plant "whose seed is in itself,” and con- tinue the species through thousands of form and quality of life." And again, years matter itself tells us nothing." The animal body is just as much the We can collect together all the constit-product of molecular force as the stalk uents of a plant and place them together and ear of corn, or as the crystal of salt and combine them as we please, but un- or sugar." And this is followed by the less we have a pre-existing seed we are melancholy conclusion that the theme absolutely powerless to obtain vegetable "will be handled by the loftiest minds life. And were it not that there are no after you and I, like streaks of morning degrees of impossibility, I might say that cloud, shall have melted into the infinite it is still more impossible for us, by any lasure of the past." The infinite azure of that is the dreary idea of noncomposition of substances, to create ani- the past! mal life. But even admitting the wild existence which this philosopher would supposition that it might be possible for have us take in exchange for " our hope us, by combinations of inorganic matter, full of immortality." to start into existence organic life, we should be no nearer the solution of the problem, which is to explain why such and such material causes should be capable of producing such effects. star-eyed Science! hast thou wandered there, To waft us home the message of despair? The Now, if all Professor Tyndall had said If therefore this be so, and the natural was that matter has the promise and pophilosopher is obliged to confess his ig-tency of every form and quality of matenorance of the nature of ultimate mate-rial existence, he would have been strictrial causes, he has no right whatever to ly justified by facts. For undoubtedly all speak of them, or even hint at them, the material universe has been built up as self-created and self-sufficient to pro- by the combination and play of material duce not only the world of matter but the elements and force. And we believe that world of reason and intelligence. He this is so because an intelligent Creator knows nothing about them, and all that endowed those elements, with the mystehe can predicate of them is conjecture rious power. But Professor Tyndall and unverified hypothesis. And surely speaks of "every form and quality of he incurs a very grave responsibility if, life," including, therefore, human life, notwithstanding this, he throws out ut- and all its manifestations of intelligent terances which, however vague and un-thought. Or if he did not mean this he warranted, the mass of mankind will be- ought to have distinctly said so. lieve to be justified by the conclusions of animal body, no doubt, is the product of science, and which, if true, would abso-molecular force as much as the stalk and lutely destroy religion, and even destroy ear of corn, but what of animal life? We the very notion of moral responsibility. can decompose an animal body into its I do think that we have a right to com- constituent elements by analysis; but by plain that a man like Professor Tyndall no synthesis, however we may contrive should, in the chair of the British Asso- and unite these elements in the same exciation at Belfast, have used language act proportions as they existed in the which it is difficult by any charitable con- living body, can we produce life. This struction to exculpate from this charge is something superadded which tranof teaching mere materialism in its most scends the utmost powers of chemistry uncompromising form. Unless it were to effect. In fact, chemistry cannot acfor the purpose of aiming a blow at the-count for the efficient cause of the growth ism, by which I mean the belief in a Su- of a single blade of grass, still less for the preme Intelligence, I know not for what growth and spontaneous motion of a sinpurpose he paraded the names of Leucip-gle animal, although the very lowest in pus and Democritus, and Epicurus and the scale. Professor Tyndall substitutes Lucretius, and dwelt at such length on an arbitrary hypothesis for an experithe doctrine of atoms and molecules. He mental fact, and this I call utterly unphilsaid, "Abandoning all disguise, the con-osophical. I know that he has since confession that I feel bound to make before fessed that his materialistic theory "does you is that I prolong the vision backward not commend itself to his mind in hours across the boundary of the experimental of clearness and vigour," and that "in evidence, and discern in that matter which the presence of stronger and healthier we in our ignorance, and notwithstand-thought it even dissolves and disappears." ing our professed reverence for its Crea- Why, then, did he in the chair of the tor, have hitherto covered with oppro- British Association prefer to proclaim brium, the promise and potency of every 'to the world the fancies of his weak and |