# Littell's Living Age/Volume 131/Issue 1696/The New-Found Enemies of Man

From The Spectator.
THE NEW-FOUND ENEMIES OF MAN.
Civilized man, having conquered the most visible of his enemies, — savages and wild beasts of the more visible and tangible kind— has nevertheless not by any means attained a state of even comparative security. It is true that the newest of his enemies are minute, sometimes even of the more or less microscopic kind, but Sir Wilfrid Lawson was not far wrong when he said that an invasion from the Colorado beetle was much more to be feared than an invasion from Germany or France. With regard to the human invader, we have at least the "streak of silver sea" and a powerful navy to rely on; but with regard to the Colorado beetle, it seems that it would take its passage just as cheerfully on our own ironclads as on any other craft by which it could cross the Atlantic, and would probably have an excellent chance of landing successfully on our shores from the very navy which defends them against a less formidable foe. The Canadian minister of agriculture has just assured Lord Carnarvon that this destructive creature not only flies, but navigates smooth water, and travels — of course without charge — by railway carriages, and on all sorts of ships. Not only so, but the creature seems to have a wonderful power either of subsiding into a kind of inert life when it cannot get food suitable for it, or of getting enough food to sustain life in all sorts of situations where we should suppose that it could get none, and then returning to full activity and vigor whenever it finds itself in the neighborhood of suitable nourishment. Indeed, the Canadian minister of agriculture declares that the notion of preventing the introduction of the Colorado potato-beetle into any part of the earth with which human beings keep up active communication is perfectly chimerical. All that can be done to keep him under is to destroy the eggs and larva as effectually as possible as soon as their existence is detected, and before the beetle itself is hatched. By a sufficient expenditure of money and time, says the Canadian minister of agriculture, this may be fairly done. The eggs deposited on the under side of the leaves of the potato-vine should be destroyed as soon as discovered. The buds and leaves should be watched for grubs, which may be destroyed by the use of "Paris green," and the beetle itself should be crushed whenever seen. These remedies are, he says, fairly effectual in keeping the plague under, though of course they will add materially to the cost of potato-culture, and enhance the price of an article which it takes such elaborate care to protect. Nor is the Colorado beetle the only minute foe whose invasion we have to fear. Six of the Southern States of America are concerting measures against grass-hoppers, which infest them with a milder form of the same evil caused by the great locust invasions from which the coasts of the Mediterranean have so often suffered. Then, again, the husbandmen of the vine, in vine-growing countries, have to provide against the phylloxera plague, and the cultivators of silkworms have to provide against the pibrine plague. Worse still, there are small organisms of various kinds which are but too apt to supplant the proper ferments in all processes of fermentation, and which, if they get into the malt, spoil the beer, and if into the grape-juice, spoil the wine, and against these practically invisible enemies all sorts of expensive precautions have to be used. Lastly, and most important of all, there are certain spores which grow and multiply rapidly ​when fed on animal blood, and which produce the various diseases known as blood-poisoning of various kinds. There is the seed whose growth causes cholera, and another whose growth causes scarlet fever, and another whose presence means typhoid, and another which results in splenic fever, and another which generates small-pox, and probably many more besides, which grow at the expense of animal life or health, — of some of which Professor Tyndall has given a graphic account in the paper on fermentation in the November Fortnightly. Unquestionably, either the minute organic world is beginning to avail itself of the great advantages which its all but invisibility gives it in competing with men, or if it is only doing now what it has always done, but what is only just beginning to be understood; a greater importance is now attached to its proceedings, partly because the danger is understood, and partly, — perhaps even more, — because the weaker constitution of modern man is now so much protected against these dangers that the race suffers more, though the individuals suffer less. Of course it is obvious that, when fewer effective causes are at work to thin out the stock, those which injure it, without diminishing its fertility, tend to render it more sensitive to all external influences for the future, and therefore make the very disease against the power of which the new remedies or alleviations have been found, more menacing in some respects to the health of the race, though less so to the individuals who suffer from it, than it was at a time when it was more generally fatal. It may well be that the very knowledge which science has gained of the new dangers to which man is subject, has rendered these diseases of greater physical consequence by diminishing their fatality. The more delicate, better-guarded, longer-lived, but more sensitive constitutions which science has taught us how to protect to an average age beyond that to which even the healthy lived in former times, are necessarily more overshadowed by the physical ills of which we know so much more than our ancestors ever were, — not only because of our new knowledge, but because the tenderer inherited constitution, which has been piloted through so many dangers, is more keenly alive to such dangers than were the more hardy constitutions which had survived in spite of running the gauntlet of much more fatal ills. Modern man, whose food and drink are beset by Colorado beetles and phylloxera, whose clothing is threatened by pibrine, and whose life itself is haunted by all sorts of minute spores which so feed on his blood as to generate fever, cholera, and a great variety of plagues, is obviously in one respect not the better, but the worse for the knowledge which teaches him how to evade the worst consequences of these plagues. He has less to fear from them individually, but they have more part in him than they had when they produced more deadly results. They have inoculated him, and though they count fewer victims slain, they transmit into a remoter future the weakness and suffering which they cause. The race of men whom the common germ-poisons no longer kill off retains more of the stamp of their paralyzing effects than the race of men which succumbed at once to the first onset of the unknown foe.
This is why we cannot altogether share the enthusiasm, and can by no means adopt the sentiment, of that somewhat declamatory peroration to Professor Tyndall's Glasgow audience which ends the lecture published in the last Fortnightly. "This preventible destruction," says Professor Tyndall, referring to the havoc caused by germs of disease floating about the air, "is going on to-day, and it has been permitted to go on for ages, without a whisper of information regarding its cause being vouchsafed to the suffering, sentient world. We have been scourged by invisible thongs, attacked from impenetrable ambuscades, and it is only to-day that the light of science is being let in upon the murderous dominions of our foes. Men of Glasgow, facts like these excite in me the thought that the rule and governance of this universe are different from what we in our youth supposed them to be, — that the inscrutable Power, at once terrible and beneficent, in whom we live and move and have our being and our end, is to be propitiated by means different from those usually resorted to. The first requisite towards such propitiation is knowledge; the second is action, shaped and illuminated by that knowledge. Of knowledge we already see the dawn, which will open out by-and-by to perfect day; while the action which is to follow, has its unfailing source and stimulus in the moral and emotional nature of man, — in his desire for present well-being, in his sense of duty, in his compassionate sympathy with the sufferings of his fellow-men." And the drift of all this rather excited eloquence was not merely what is here implied; the true clue is given by a previous passage, in which it is intimated that man ought to seek this all-potent knowledge at the ​expense of violence done to almost any kindly sympathy, though not "sympathy with fellow-men." Professor Tyndall had described how the origin and rationale, though not the cure, of certain painful diseases had been discovered, partly by the use of the microscope, partly by inoculating certain living creatures with the most terrible of those diseases at various stages; and this triumphant outburst over the results which Professor Tyndall anticipates in his scientific vision, — they are not yet attained, — is meant in great degree to persuade his audience that science must be allowed to be a law unto itself, — excepting, we suppose, it should invade the life of man himself with its experimentation, nor do we see that Professor Tyndall suggests ground for even this limitation, — in endeavoring to ascertain the sources of human suffering, and the remedies or alleviations which may be applied. Leave it alone, he says, — don't reproach it with cruelty because it causes a certain amount of limited suffering, — and "its dawn will open out by-and-by to perfect day." Now, our answer to that is twofold, — first, that it is quite certain that it will not open out to perfect day, but at best to a less dim twilight; and next, that the access of twilight so gained, in ninety-nine cases out of a hundred, instead of leading to action which extinguishes the evil, will only lead to action which will attenuate it to the individual at the expense of the race. That, of course, is no reason at all why this knowledge should not be diligently sought, and sought with all the fervor of Professor Tyndall himself, unless it is sought at the cost of principles and sympathies which are as precious as human life itself, and far more precious than a slight extension of the average term of life to individuals. But the dimness of our knowledge, — the uncertainty whether even our clearest knowledge of ills will suggest any adequate remedy for them, — the absolute certainty that the knowledge which saves and protects the weak does tend to lower the standard of complete health in the future of our race, even while it increases our available resources against individual ailments, should, we think, help to make us acquiesce gladly in every restriction which the healthy moral nature of man imposes on the sources of discovery, and to warn us that far more evil than good may come of the assumption that to the genuine search after knowledge, no means, however revolting to our nature, is forbidden. If we might be permitted to alter Professor Tyndall's address to the "men of Glasgow" so as to make it suit the impression which his lecture and the discussion to which he refers have made upon ourselves, we should couch it in terms something like these: "Preventible destruction is going on to-day, and it has been permitted to go on for ages, without a whisper of information regarding its cause being vouchsafed to the suffering, sentient world. We have been scourged by invisible thongs, attacked from imperceptible ambuscades, and it is only to-day that the light of science is being let in upon the dominions of our seeming foes. Even now that it is let in, its result is by no means unadulterated good. Destruction prevented, means, too often, weakness transmitted. The invisible thongs which scourged one generation not unfrequently saved the next from the scourges of thongs more frightful still. While the total result for good in human life has been to extend by a few years the average age of man in civilized countries, and to extinguish a good many of the worst spasms of human anguish, that result probably includes quite as much effect in transmitting hereditary feebleness or taints to future generations, as in saving men altogether from the assaults of disease. Let science grow as it will, human life will continue to be hemmed in by all sorts of visible and invisible ills with the totality of which we must never cease to struggle, but with which our struggle is never likely to be, on the whole, much more successful than it now is. What we gain in one way, we shall probably lose in another; as some of our unknown foes are discovered and defeated, the very means which discover and defeat them will make other foes more formidable; and after all, our chief resource will lie in the future, as it does in the present, in the undaunted courage of our fight, the unquailing fortitude of our endurance, and in our firm faith in God here, and a higher life with Him beyond. Considerations like these excite in us the thought that the rule and governance of this "universe is not very different from what in our youth we supposed it to be, — that the Power, at once terrible and beneficent, in whom we live and move and have our being and our end, is not to be propitiated by any mere advance of knowledge. The first requisite towards such propitiation is right action in the light we have, — the second, to increase that light wherever we can do so by means which do not lower us in God's eyes and our own. The desire to know, like almost all other desires, ​if unbridled, may lead men into actions which would make knowledge sin. It is well, therefore, to realize that even some of the most beneficent results of knowledge have yielded consequences of a double kind, have weakened the winnowing power of physical disease on the human stock, by virtue of the very principle by which they alleviated its assaults. This should teach us that if at anytime we have to choose between extending knowledge at the expense of what is noblest in us, and leaving a window closed which we might otherwise open into the secrets of nature, we may be quite safe in preferring the latter course, if only because to violate our moral ideal is a certain and irreparable evil, while the extension of knowledge is at best in comparison but an uncertain good."