William Stanley Jevons

“ Now, when trade is left free it gives rise to division of labour, not only between town and town, county and county, but between the most distant nations of the earth. Thus is created what may be called the territorial division of labour. Commerce between nation and nation is not only one of the best means of increasing wealth and saving labour, but it brings us nearer to the time when all nations will live in harmony, as if they were but one nation. ”

“ A single absolute conflict between fact and hypothesis, is fatal to the hypothesis; falsa in uno, falsa in omnibus.
Seldom, indeed, shall we have a theory free from difficulties and apparent inconsistency with facts. Though one real inconsistency would overturn the most plausible theory, yet there is usually some probability that the fact may be misinterpreted, or that some supposed law of nature, on which we are relying, may not be true. ”

“ The angler goes to the river in the early morning or the evening, when the fish will bite; the farmer makes hay while the sun shines; the miller grinds corn when the breeze is fresh, or the stream full; and the skipper starts when wind and tide are in his favour. By long experience farmers have found out the best time of year for doing every kind of work: seed is sown in autumn or spring; manure is carried in winter when the ground is frozen; hedges and ditches are mended when there is nothing else to do, and the harvest is gathered just when it is ripe, and the weather is fine. ”

“ There is no more convincing proof of the soundness of knowledge than that it confers the gift of foresight. Auguste Comte said that “Prevision is the test of true theory;” I should say that it is one test of true theory, and that which is most likely to strike the public attention. Coincidence with fact is the test of true theory, but when the result of theory is announced before-hand, there can be no doubt as to the unprejudiced spirit in which the theorist interprets the results of his own theory. ”

“ This is the old fallacy of the Mercantile Theory, which was to the effect that a country becomes rich by bringing gold and silver into it. It is an absurd fallacy, because we can get no benefit by accumulating stocks of gold and silver. In fact, to keep precious metals causes a loss of interest upon their value; people who are rich may afford to have costly plate, and the pleasures they derive from it may be worth the interest. But to have more gold, or silver money than is just sufficient to make the ordinary payments of trade causes dead loss of interest. ”

“ But no one can suppose that patient labour alone will invariably lead to those conspicuous results which we attribute to genius. In every branch of science, literature, art, or industry, there are thousands of men and women who work with unceasing patience, and thereby ensure moderate success; but it would be absurd to suppose that equal amounts of intellectual labour yield equal results. A Newton may modestly attribute his discoveries to industry and patient thought, and there is reason to believe that genius is unconscious and unable to account for its own peculiar powers. ”

“ We ought always to bear in mind that the mean of any series of observations is the best, that is, the most probable approximation to the truth, only in the absence of knowledge to the contrary. The selection of the mean rests entirely upon the probability that unknown causes of error will in the long run fall as often in one direction as the opposite, so that in drawing the mean they will balance each other. If we have any reason to suppose that there exists a tendency to error in one direction rather than the other, then to choose the mean would be to ignore that tendency. ”

“ If an employment is in itself comparatively pleasant, it attracts many who would not otherwise go into it at the current wages. Thus, officers of the army and navy are not on the average highly paid; but there is never any difficulty in finding men willing to be officers, because the work is thought to be easy, and there is honour and power attaching to it. On the other hand, a good butcher makes high wages, because his business is a greasy one, besides being thought to be cruel, and a clever man must be attracted to it by good earnings. ”

“ THEORY OF APPROXIMATION. In order that we may gain a true understanding of the kind, degree, and value of the knowledge which we acquire by experimental investigation, it is requisite that we should be fully conscious of its approximate character. We must learn to distinguish between what we can know and cannot know—between the questions which admit of solution, and those which only seem to be solved. Many persons may be misled by the expression exact science, and may think that the knowledge acquired by scientific methods admits of our reaching absolutely true laws, exact to the last degree. ”

“ We must now try to make out how wealth is shared among those who have a hand in producing it. The requisites of production, as we have seen, are land, labour, and capital; if these were all supplied by the same person, no doubt the produce ought all to belong to him, with the exception of what is taken by the government as taxes. But, in a state of society such as exists at present, the labourer seldom owns all the land and capital he uses; he goes to work on another man's farm, or in another man's factory; he lives in another man's house, and often eats another man's food ”

“ So far as object is different from object, knowledge is useless and inference impossible. But so far as object resembles object, we can pass from one to the other. In proportion as resemblance is deeper and more general, the commanding powers of knowledge become more wonderful. Identity in one or other of its phases is thus always the bridge by which we pass in inference from case to case; and it is my purpose in this treatise to trace out the various forms in which the one same process of reasoning presents itself in the ever-growing achievements of Scientific Method. ”

“ Every tax ought to be so contrived as both to take out and to keep out of the pockets of the people as little as possible over and above what it brings [Pg 131] into the public treasury. This is the maxim of economy. Thus, a tax ought not to be imposed if it would require a great many officers to collect it, and thus waste much of what is collected, or if it disturbs trade and makes things dearer than they would otherwise be. Again, the government ought not to cause people to lose time and money in paying the taxes, because this is just as bad for them as if they paid so much more taxes. ”

“ There must, indeed, be no prejudice or bias distorting the mind, and causing it to pass over the unwelcome results of experiment. There must be that scrupulous honesty and flexibility of mind, which assigns adequate value to all evidence; indeed, the more a man loves his theory, the more scrupulous should be his attention to its faults. It is common in life to meet with some theorist, who, by long cogitation over a single theory, has allowed it to mould his mind, and render him incapable of receiving anything but as a contribution to the truth of his one theory. ”

“ All that we need to secure additions to our knowledge of nature is the erection of great laboratories, museums, and observatories, and the offering of pecuniary rewards to those who can invent new chemical compounds, detect new species, or discover new comets. Doubtless this is not the real meaning of the eminent men who are now urging upon Government the endowment of physical research. They can only mean that the greater the pecuniary and material assistance given to men of science, the greater the result which the available genius of the country may be expected to produce. ”

“ People actually refuse to see that wealth must be increased by producing it where it can be produced most easily and plentifully. Each trade, each town, each nation must furnish what it can yield most cheaply, and other goods must be bought from the places where they also can be raised most easily.
Political economy teaches us to look beyond the immediate effect of what we do, and to seek the good of the whole community, and even of the whole of mankind. The present prosperity of England is greatly due to the science which Adam Smith gave to the world in his "Wealth of Nations." ”

“ There is no doubt in lightning as to the point it shall strike; in the greatest storm there is nothing capricious; not a grain of sand lies upon the beach, but infinite knowledge would account for its lying there ”

“ But Arago, who had both discovered the phenomenon and personally investigated its conditions, declined to put forward publicly any theory at all.
At the same time we must not suppose that the truly philosophic mind can tolerate a state of doubt, while a chance of decision remains open. In science nothing like compromise is possible, and truth must be one. Hence, doubt is the confession of ignorance, and involves a painful feeling of incapacity. But doubt lies between error and truth, so that if we choose wrongly we are further away than ever from our goal. ”

“ Everybody who wishes to understand the necessity for capital, and the way capital serves us, should read this tale of Miss Martineau, and then go on to her other tales about Political Economy.
We can hardly say that capital is as requisite to production as land and labour, for the reason that capital must have been the produce of land and labour. There must always, indeed, be a little capital in possession, even though it be only the last meal in the stomach, before we can produce more. ”

“ Had the science of numbers been studied for no other purpose, it must have been developed for the calculation of probabilities. All our inferences concerning the future are merely probable, and a due appreciation of the degree of probability depends upon a comprehension of the principles of the subject. I am convinced that it is impossible to expound the methods of induction in a sound manner, without resting them upon the theory of probability. Perfect knowledge alone can give certainty, and in nature perfect knowledge would be infinite knowledge, which is clearly beyond our capacities. ”

“ It is sad, again, to see thousands of persons trying to improve their positions by means which have just the opposite effect, I mean by strikes, by refusing to use machinery, and by trying, in various ways, to resist the production of wealth. Working men have made a political economy of their own: they want to make themselves rich by taking care not to produce too much riches. ”

“ Such may not generally be the reflections of men of science, but I believe that we may thus describe the secret feelings of fear which the constant advance of scientific investigation excites in the minds of many. Is science, then, essentially atheistic and materialistic in its tendency? Does the uniform action of material causes, which we learn with an ever-increasing approximation to certainty, preclude the hypothesis of a benevolent Creator, who has not only designed the existing universe, but who still retains the power to alter its course from time to time? ”

“ To apprehend the truth of special cases of inference does not constitute logic; we must apprehend them as cases of more general truths. The object of all science is the separation of what is common and general from what is accidental and different. In a system of logic, if anywhere, we should esteem this generality, and strive to exhibit clearly what is similar in very diverse cases. Hence the great value of general symbols by which we can represent the form of a reasoning process, disentangled from any consideration of the special subject to which it is applied. ”

“ Society, it is supposed, has now assumed so highly developed a form, that what was accomplished in past times by the solitary exertions of a great intellect, may now be worked out by the united labours of an army of investigators. Just as the well-organised power of a modern army supersedes the single-handed bravery of the mediæval knights, so we are to believe that the combination of intellectual labour has superseded the genius of an Archimedes, a Newton, or a Laplace. ”

“ No apparent limit exists to the success of scientific method in weighing and measuring, and reducing beneath the sway of law, the phenomena both of matter and of mind. And if mental phenomena be thus capable of treatment by the balance and the micrometer, can we any longer hold that mind is distinct from matter? Must not the same inexorable reign of law which is apparent in the motions of brute matter be extended to the subtle feelings of the human heart? Are not plants and animals, and ultimately man himself, merely crystals, as it were, of a complicated form? ”

“ He who errs surely diverges from law, and it might be deemed hopeless out of error to draw truth. One of the most remarkable achievements of the human intellect is the establishment of a general theory which not only enables us among discrepant results to approximate to the truth, but to assign the degree of probability which fairly attaches to this conclusion. It would be a mistake indeed to suppose that this law is necessarily the best guide under all circumstances. Every measuring instrument and every form of experiment may have its own special law of error ”