PHYSICAL AND MORAL LAW.*

[MST NOTICE.1

tres medici, ibi duo athei," says the proverb. And the explanation of this general belief seems to lie in the fact that the constant study of physiology and therapeutics fills the mind with such an endless chain of physical sequences as to unfit it naturally for the great step from the phenomenal world to its First Cause. The question "Whence did all this come, how

• On the Difference between Physical and Moral Law. The Fernley Lecture for 1883. By William Arthur. London : T. Woolmer. 1883.

does my particular science Et in with the general scheme of Nature, what is its import, what its relations to the other parts of Nature's scheme ? " occurs as little to one who is engaged in microscopically studying the laws of heart disease or the structure and functions of the liver, as the history of the -developments and changes of dress and the origin of the present fashions occurs to the average tailor ? The work of each is practical, and connected with what is immediately before his eyes. The physician's interest is in the details, and not in their causes, so far as those causes are outside his practical work ; and consequently the very conception of the first cause, as being entirely outside the range of his thoughts, becomes to him one requiring painful effort,—too painful, in many cases, to be made at all.

Here, then, are two aspects in which a rule may be looked at, —firstly, what is the exact nature of the rule ; secondly, whence it comes, why is it the rule ? Both these questions call for an answer, and the answer to each gives real knowledge; One class of mind and one train of thought leads to the one, a different one to the other. And in respect of the laws of the physical universe, there can be no doubt that it is the " doctor's " habit of mind—as we have explained it above— which is in vogue now. The details of physical phenomena and their general rules of occurrence are becoming so closely and minutely known as to fill the human mind, and to leave it little capacity for dealing with that other aspect of natural law which asks the questions :—" Why do such forces act in such a way P Whence comes the rule ? What is it which gives such a combination of phenomena the power of producing this third phenomenon ? What is it that has fitted physical forces for the marvellous variety of results, useful for our species and for the furtherance of life, which natural law, both in itself and as directed by man, produces ?" But many modern thinkers, not content with "brushing aside" such questions, as the author of the book before us expresses it, have proceeded to excuse their procedure in so doing by roundly declaring that these questions -cannot he answered, and that the phenomenon and its general rules of succession are all that is meant or revealed to us by natural law, and that the "cause" of a phenomenon has no meaning beyond that of the antecedent phe- nomenon, and law no meaning beyond uniformity of succession. Anything beyond this it is waste of time to inquire into.

The book now before us is especially remarkable for its able and detailed insistence upon that other side of physical law which modern men of science would drop out of sight. The effect of the writings of Huxley and Tyndall in this matter is due far more to the dazzling array of physical facts and- rules which they show us, than to their reasoning against our knowledge of anything beyond.. They hold up the tangible and verifiable facts of experience before us, much as idol- worship tempted the Jews. A god whom the people could see and touch rivetted the imagination, and satisfied them more readily than an invisible God, to be conceived only by effort of mental imagination ; and similarly, the complacent verifica- tion or physical experiment is more resting to the mind, than the constant strain of looking at the mystery beyond. Mr. Arthur, then, is chiefly occupied in showing how unmietake- ably the mind is forced, if it looks steadily at the matter, to recognise a reality beyond the phenomena, law beyond observed uniformities, cause behind phenomenal succession. While Tyndall dazzles us by the innumerable minute successions, and fills the mind with quantity, Mr. Arthur takes one, holds it up to the light, and bids us observe its quality and meaning. St. Thomas Aquinas speaks of curiositas as the opposite quality to studiositas. Tyndall satisfies the former by infinite variety and multiplicity of objects. Mr. Arthur appeals to the latter that the meaning of even one of them may be fully understood by careful and concentrated reflection. Mr. Arthur's book is called On the Difference between Physical and Moral Law, but its real subject is not so much the difference between the two as the import of each. We shall confine our first notice of it mainly to his suggestions on physical law.

Ntav, in. the first place, the very fact that the term " law " has come to be applied to the operation of natural forces indicates the tendency of the mind to see something in their constancr beyond a mere fact, to infer a giver and impresser of the law. And the term is so suggestive of this, that Mr. Lewes said it should be dropped, and the word " method " substituted. And uthers of the phenomenist school, unable entirely to get rid of the conception, tried to explain it as involving no more than "general facts" in nature governing natural forces. On this Mr. Arthur writes as follows :—

" Now, far be it from me to say that laws do not govern forces, but general facts do not govern them. General facts are the product of forces, and depend on them, instead of presiding over them. When in the same breath those so-called laws for which we are gravely coun- selled to give up the study of causes and designs, in order to set laws alone before us as the sole object of research, because, forsooth, they are only accessible—when these are called by three names which mean things so broadly distinguishable as conditions, general facts, and laws—I feel two things, first, that if accessible to the rest of us, they elude the writer ; and, secondly, that while such writing is very like that of the Positivists, it is very unlike either sober science or sound philosophy. A mere general fact is not enough to make what all mean by a physical law. It is a general fact that persons going from London to Edinburgh set out northward, but it is no law. Any gentleman may face westwards and go by Bristol. To be the index of a physical law, a fact needs to be more than general,—to be universal and without exception. The fact that the mariner's compass points northerly and southerly is such a fact. It indicates a physical law ; and by a very usual figure of speech is called a law. A very ordinary description of a physical law is an observed order of facts! This formula rightly assumes that not a fact only, but facts must be in view ; and not facts in promiscuous relations, but facts set in order. But to make facts set in order into a law, it requires that the order shonld be observed.' If a law is an 'observed' order of facts, what is an unobserved order ? Before the day of Harvey, the circulation of the blood was an order of facts as much as it is to-day. But it had never been observed. Was there, then, no law of the circulation of the blood ? Before Newton, gravitation was an order of facts as much as it has been since. Did he make the law when he observed the order of facts ? "

This passage places the case on its right footing. The order is doubtless due to the law, but it is a sudden reversal of the mental process to proceed to ascribe the law to him who detects its existence. Surely the law is due to that which makes it, not that which finds it. The true process of the inquiring mind is to take note of uniformities in natural relations, until it dis-

covers-a constant principle regulating certain of them. Then the more passive operation of noting similarities gives place on a sudden to the inference,—there is a reason for these similari- ties, they are due to a common agency. They do not end in themselves; they indicate something beyond. Thus order is not law, but it may indicate law. And when the law is seen to be subservient to design, the mind steps farther to the conclu- sion that "the embodiment of rules of proportion and modes of procedure in agents themselves incapable of design, purpose, or adjustment represents a ruler capable of all three." The whole thing is a process upwards, an investigation of Nature, and not the mere record of general facts. It is a looking at the

facts with a view to getting beyond facts. The law is not the facts, it is something beyond, which is a conclusion, an inference from the facts taking our knowledge a step higher.

The fact of constancy in physical relations points to some reason beyond those relations themselves, regarded

as phenomena. The fact of bodies being attracted towards each other with a certain velocity is one thing. It is, if you please, a phenomenon. But the truth that the velocity of the attraction bears in every case a constant ratio to the mass and the distance,—this is not, physically speaking, a fact

only. It is a property of the physical facts, indicating the pre- sence of an invariable rule of procedure ; and the rule, as being discovered by us from below to be already in existence, and as being no artificial classification of facts on our part, is inferred by us to be a law imposed from above. Constancy in relations and order in facts are taken as resulting from a law, and conse- quently as holding good outside the sphere of our observation. And if order and design lead us on to the conception of the mind

and power of-. the law-giver, that is a step, further still. The confusion implied in supposing that when the law is ascertained, we still have only a group of phenomenal facts, and nothing beyond, is parallel to that which leads the saute teachers to say that in causation we know no more than phenomenal sequence.

The fact is precisely the contrary. When oxygen and hydro- gen are in due course turned into water the knowledge

that is especially forced on us is not the succession between the electric spark and the appearance of water, but the existence in these elements of certain invisible properties adapting them for the operation. True, we know of these properties only from their effects, but we are nevertheless certain that they are not the effects. Take, again, the phenomena of animal and vegetable

growth. What we know least about these "hopelessly dark

processes," as Da Bois Reymond has called them, are the details of phenomenal succession ; what we know best is that there are properties in the embryo which empower it to develop into the particular species of which it is the embryo. "Millions of men,"

writes Mr. Arthur, "who could not tell an acorn from a chestnut know perfectly, know with a knowledge fit to be acted upon, that an acorn will grow oak, and that chestnut will not. It is its invisible power, its oak-forming prerogative, that constitutes the one thing about it best known." And this is not to know observed phenomena or phenomenal succession, but to infer the existence of something behind both. To confine our conception of law, then, to the facts it accounts for, and to confine our conception of causation to groups of phenomena, one following immediately upon the other, is simply to empty the words "law" and "cause" of all their meaning, and to stop the human mind short of its most natural, spontaneous, and certain conclusions. This conclusion is stated by Mr. Arthur, in a forcible passage, which we proceed to quote :—

" It is felt that both the question 'Why' and the answer Because have two poles, each of them by one of its ends pointing to an in- telligent origin, and by the other to an intelligent design. And as we are to give up inquiry into causes, so we must also give up dis- covering design. This is technically expressed by saying that we are not to seek for causes, either original or final. We are, be it observed, allowed to inquire into laws, always provided we empty law of the ideas most natural to the word, and think of it only as dead rule,—a rule discovered, indeed, by mind, but never set by mind. Now, this demand to give up the study of causes and designs is simply a de- mand that we shall truncate our own intellects, and do it at both ends. We, as standing by the stream of time, are to be free to in- quire as to reach after reach of its course, as to eddy, shallow, bend, and pail, and also as to fish, bird, craft, or human swimmer that may come upon its waters ; but as to that inconvenient tendency of our minds to infer that where there is a river there is-also at one end a river-head and at the other end a river-foot, we must smother that tendency till it dies out. It may be trae that there are sages dwelling at Timbactoo so deeply enveloped in mid-earth that to them it seems impossible to find a goal at either end. Yet will the human mind affirm, nevertheless, the river has a head, however far out of sight, and the river has a foot, however far out of eight If debased coin has been foisted on a nation, it is vain to say that the cause is inaccessible, and all that must be done is to endeavour to discover the law. Suppose you do discover that the law of the alloy is one portion of a base metal to three of the precious one, and that the law of the coinage is one stroke of the die to a single piece, how much have you discovered ? Enough to meet the case ? Have you either explained the origin of the phenomenon, or satisfied the nature of man which calls out for the cause ? All you have done is to point out two rules of proportion observed in the procedure, and by an easy rhetoric you have put upon those rules the name of laws. But if you think to pass off this as any real explanation, human nature pushes you and your explanation out of its way. It knows that the rule of pro- portion observed in the alloy was no cause, and that that rule itself had a cause. It knows that the cause of the rule was an intelligent being Hence does it demand to know who was the person by whose authority this rule of proportion was made into a law of procedure. To substitute law for cause is puerile thinking, as much as it would be to substitute method for intention, and, indeed, is a closely analogous blunder."

Finally, then, physical law is a conception which must lead backwards and upwards. It is no set of generalised uniformities, as the whiteness of swans may have been before the black swan was known. The discovery of the black swan was an exception to a rule, but no breach of law. If Newton's law of gravitation should begin to fail of opeiation, and if the compass should on a given occasion point to the east, it would be no mere breach of rule, no mere exceptional fact. It would reach far back. Convince us that these things have really happened, and the very contrast between the consternation it will arouse in the man of science, and the ease with which he receives the news of exception to a mere general fact—as the whiteness of swans—will reveal how wide apart were, in reality, his conceptions of law and general rule. The latter is only an assumed constancy, with no further reach ; the former carries with it the conception of energies beyond phenomena, working uniformly and constantly, and controlling the universe, The one is merely a set of facts classified from below; the other, the revelation of Power arranging facts from above.