wards France; but France has since that time given ample evidence of her ability to crush, not only Socialists, but anti-Socialists, who would impose on her a yoke which she refuses to bear.

In close connection with these utterances of Helmholtz, I place another utterance not less noble, which I trust was understood and appreciated by those to whom it was addressed.

If (said the President of the British Association in his opening address in Dublin) we could lay down beforehand the precise limits of possible knowledge, the problem of physical science would be already half solved. But the question to which the scientific explorer has often to address himself is not merely whether he is able to solve this or that problem; but whether he can so far unravel the tangled threads of the matter with which he has to deal as to weave them into a definite problem at all. . . . If his eye seem dim, he must look steadfastly and with hope into the misty vision, until the very clouds wreathe themselves into definite forms. If his ear seem dull, he must listen patiently and with sympathetic trust to the intricate whisperings of Nature-the goddess, as she has been called, of a hundred voices-until here and there he can pick out a few simple notes to which his own powers can resound. If, then, at a moment when he finds himself placed on a pinnacle from which he is called upon to take a perspective survey of the range of science, and to tell us what he can see from his vantage-ground; if at such a moment after straining his gaze to the very verge of the horizon, and after describing the most distant of well-defined objects, he should give utterance also to some of the subjective impressions which he is conscious of receiving from regions beyond; if he should depict possibilities which seem opening to his view; if he should explain why he thinks this a mere blind alley and that an open path; then the fault and the loss would be alike ours if we refused to listen calmly, and temperately to form our own judgment on what we hear; then assuredly it is we who would be committing the error of confounding matters of fact with matters of opinion, if we failed to discriminate between the various elements contained in such a discourse, and assumed that they had been all put on the same footing.

While largely agreeing with him, I cannot quite accept the setting in which Professor Virchow places the confessedly abortive attempts to secure an experimental basis for the doctrine of spontaneous generation. It is not a doctrine 'so discredited' that some of the scientific thinkers of England accept as the basis of all their views of life.' Their induction is by no means thus limited. They have on their side more than the reasonable probability' deemed sufficient by Bishop Butler for practical guidance in the gravest affairs, that the members of the solar system which are now discrete once formed a continuous mass; that in the course of untold ages, during which the work of condensation went on through the waste of heat in space, the planets were detached; and that our present sun is the residual nucleus of the flocculent or gaseous ball from which the planets were successively separated. Life, as we define it, was not possible for æons subsequent to this separation. When and how did it appear? I have already pressed this question, but have received no answer.13 If, with Professor Knight, we regard the Bible account of the introduction of life upon the earth as a poem, not as a statement of fact, where are we to seek for guidance as to 1 In the Apology for the Belfast Address, the question is reasoned out,

the fact? There does not exist a barrier possessing the strength of a cobweb to oppose to the hypothesis which ascribes the appearance of life to that 'potency of matter' which results in natural evolution.14 This hypothesis is not without its difficulties, but they vanish when compared with those which encumber its rivals. There are various facts in science obviously connected, and whose connections we are unable to trace; but we do not think of filling the gap between them by the intrusion of a separable spiritual agent. In like manner though we are unable to trace the course of things from the nebula, where there was no life in our sense, to the present earth where life abounds, the spirit and practice of science pronounce against the intrusion of an anthropomorphic creator. Theologians must liberate and refine their conceptions or be prepared for the rejection of them by thoughtful minds. It is they, not we, who lay claim to knowledge never given to man. Our refusal of the creative hypothesis is less an assertion of knowledge than a protest against the assumption of knowledge which must long, if not always, lie beyond us, and the claim to which is a source of perpetual confusion.' At the same time, when I look with strenuous gaze into the whole problem as far as my capacities allow, overwhelming wonder is the predominant feeling. This wonder has come to me from the ages just as much as my understanding, and it has an equal right to satisfaction. Hence I say, if, abandoning your illegitimate claim to knowledge, you place, with Job, your forehead in the dust and acknowledge the authorship of this universe to be past finding out-if having made this confession, and relinquished the views of the mechanical theologian, you desire, for the satisfaction of feelings which I admit to be in great part those of humanity at large, to give ideal form to the Power that moves all things-it is not by me that you will find objections raised to this exercise of ideality, when consciously and worthily carried out.

Again, I think Professor Virchow's position, in regard to the question of contagium animatum, is not altogether that of true philosophy. He points to the antiquity of the doctrine. It is lost,' he says, 'in the darkness of the middle ages. We have received this name from our forefathers, and it already appears distinctly in the sixteenth century. We possess several works of that time which put forward contagium animatum as a scientific doctrine, with the same confidence, with the same sort of proof, with which the "Plastidulic soul" is now set forth.'

These speculations of our forefathers' will appeal differently to different minds. By some they will be dismissed with a sneer; to others they will appeal as proofs of genius on the part of those who enunciated them. There are men, and by no means the minority,

14 We feel it an undeniable necessity,' says Professor Virchow, 'not to sever the organic world from the whole, as if it were something disjoined from the whole.' This grave statement cannot be weakened by the subsequent pleasantry regarding 'Carbon & Co.'

who, however wealthy in regard to facts, can never rise into the region of principles; and they are sometimes intolerant of those who can. They are formed to plod meritoriously on the lower levels of thought, unpossessed of the pinions necessary to reach the heights. They cannot realise the mental act-the act of inspiration it might well be called-by which a man of genius, after long pondering and proving, reaches a theoretic conception which unravels and illuminates the tangle of centuries of observation and experiment. There are minds, it may be said in passing, who at the present moment stand in this relation to Mr. Darwin. For my part, I should be inclined to ascribe to penetration rather than to presumption the notion of a contagium animatum. He who invented the term ought, I think, to be held in esteem; for he had before him the quantity of fact, and the measure of analogy, that would justify a man of genius in taking a step so bold. Nevertheless,' says Professor Virchow, ‘no one was able throughout a long time to discover these living germs of disease. The sixteenth century did not find them, nor did the seventeenth, nor the eighteenth.' But it may be urged, in reply to this, that the theoretic conjecture often legitimately comes first. It is the forecast of genius which anticipates the fact and constitutes a spur towards its discovery. If instead of being a spur the theoretic guess rendered men content with imperfect knowledge, it would be a thing to be deprecated. But in modern investigation this is distinctly not the case; Darwin's theory, for example, like the undulatory theory, has been a motive power and not an anodyne. At last,' says Professor Virchow, in the nineteenth century we have begun little by little really to find contagia animata.' So much the more honour is due to those who, three centuries in advance, so put together the facts and analogies of contagious disease as to divine its root and character. Professor Virchow seems to deprecate the 'obstinacy' with which this notion of a contagium vivum emerged. Here I should not be inclined to follow him; because I do not know, nor does he tell me, how much the discovery of facts in the nineteenth century is indebted to the stimulus derived from the theoretic discussions of preceding centuries. The genesis of scientific ideas is a subject of profound interest and importance. He would be but a poor philosopher who would sever modern chemistry from the efforts of the alchemists, who would detach modern atomic doctrines from the speculations of Lucretius and his predecessors, or who would claim for our present knowledge of contagia an origin altogether independent of the efforts of our forefathers' to penetrate this enigma.

Finally, I do not know that I should agree with Professor Virchow as to what a theory is or ought to be. I call a theory a principle or conception of the mind which accounts for observed facts, and which helps us to look for and predict facts not yet observed. Every new discovery which fits into a theory strengthens it. The theory is not

a thing complete from the first, but a thing which grows, as it were asymptotically, towards certainty. Darwin's theory, as pointed out nine and ten years ago by Helmholtz and Hooker, was then exactly in this condition of growth; and had they to speak of the subject to-day they would be able to announce an enormous strengthening of the theoretic fibre. Fissures in continuity which then existed, and which left little hope of being ever spanned, have been since bridged over, so that the further the theory is tested the more fully does it harmonise with progressive experience and discovery. We shall probably never fill all the gaps; but this will not prevent a profound belief in the truth of the theory from taking root in the general mind. Much less will it justify a total denial of the theory. The man of science who assumes in such a case the position of a denier is sure to be stranded and isolated. The proper attitude in my opinion is to give as nearly as possible to the theory during the phases of its growth a proportionate assent; and, if it be a theory which influences practice, our wisdom is to follow its probable suggestions where more than probability is for the moment unattainable. I write thus with the theory of contagium vivum more especially in my mind, and must regret the attitude of denial assumed by Professor Virchow towards that theory. "I must beg my friend Klebs to pardon me,' he says, 'if, notwithstanding the late advances made by the doctrine of infectious fungi, I still persist in my reserve so far as to admit only the fungus which is really proved, while I deny all other fungi so long as they are not actually brought before me.' Professor Virchow, that is to say, will continue to deny the Germ Theory, however great the probabilities on its side, however numerous the cases of which it renders a just account, until it has ceased to be a theory at all, and has become a congeries of sensible facts. Had he said, As long as a single fungus of disease remains to be discovered, it is your bounden duty to search for it,' I should cordially agree with him. But by his unreserved denial he quenches the light of probability which ought to guide the practice of the medical man. Both here and in relation to the theory of evolution excess on the one side has begotten excess on the other.

In publishing the forthcoming volume of Fragments of Science to which the foregoing article is introductory, I could not entirely ignore the criticisms which one or two amongst them have evoked. Of such strictures, however, my knowledge is incomplete, their authorship causing me to give some of them a spacious berth. Nor as regards those with which I am acquainted have I deemed it necessary to offer direct refutations. They fall spontaneously to pieces in presence of the facts here set forth.

J. TYNDALL.

VOL. IV.-No. 21.

3 I

NATIONAL INSURANCE:

A CHEAP, PRACTICAL, AND POPULAR MEANS OF ABOLISHING
POOR RATES.

6

I HAVE long hesitated before fixing on such a title as I have chosen for the present writing, from a knowledge that its very sound may induce most readers to pass it over as a matter so extravagant, impracticable, and Utopian, as to be unworthy of serious consideration. But it has been well said The Utopia of to-day is the terra cognita of to-morrow;' and feeling strongly, as I do, that the scheme I propose offers a solution of one of the most difficult and momentous social problems of our day, which has exercised the ingenuity and excited the grave anxiety of most of our serious thinkers, I venture in all modesty to offer the following argument to an unbiassed public judgment, in the confident hope of at least suggesting some new lines of thought to the many earnest students of the subject, and of leading them to believe in the possibility of a great and greatly needed amelioration in the condition of our lower classes.

I therefore most earnestly entreat their unprejudiced attention for one single hour of their thoughtful leisure to the views I am bold enough to enunciate, premising that if, on the present occasion, I direct my remarks more particularly to the economic, or, in a word, to the ratepayers' aspect of the question, it is not because I cannot fully justify and endorse them on philanthropic grounds (which indeed first suggested them to me), but because of the common-sense consideration that it is rather into the hands of ratepayers than of rate-consumers that my observations are most likely to fall. I propose to consider:

I. The general duty of providing against destitution in sickness and old age.

II. The present gross and general neglect of this duty, with its immediate causes.

JII. The failure of all past and present measures, legislative or philanthropic, to correct this neglect.

IV. National insurance, as a possible remedy.