Page:Popular Science Monthly Volume 1.djvu/662

646 this unobtrusive but speedy diffusion of knowledge, there came, along with a growing consciousness of the still-remaining deficiency, the system of State-subsidies; which, beginning with £20,000, grew, in less than thirty years, to more than a million. Yet now, after this vast progress at an ever-increasing rate, there has come the outcry that the nation is perishing for lack of knowledge. Any one not knowing the past, and judging from the statements of those who have been urging on educational organizations, would suppose that strenuous efforts are imperative to save the people from some gulf of demoralization and crime, into which ignorance is sweeping them.

How testimonies respecting objective facts are thus perverted by the subjective states of the witnesses, and how we have to be ever on our guard against this cause of vitiation in sociological evidence, may indeed be inferred from the illusions that daily mislead men in their comparisons of past with present. Returning after many years to the place of his boyhood, and finding how insignificant are the buildings he remembered as so imposing, every one discovers that in this case it was not that the past was so grand, but that his impressibility was so great and his power of criticism so small. He does not perceive, however, that the like holds generally; and that the apparent decline in various things is really due to the widening of his experiences and the growth of a judgment no longer so easily satisfied. Hence the mass of witnesses may be under the impression that there is going on a change just the reverse of that which is really going on; as we see, for example, in the notion current in every age, that the size and strength of the race have been decreasing, when, as proved by bones, by mummies, and by armor, and by the experiences of travellers in contact with aboriginal races, they have been on the average increasing.

Most testimony, then, on which we have to form ideas of sociological states, past and present, has to be discounted to meet this cause of error; and the rate of discount has to be varied according to the epoch, and the subject, and the witness.

Beyond this vitiation of sociological evidence by general subjective states of the witnesses, there are vitiations due to more special subjective states. Of these, the first to be noted are those which foregone conclusions produce.

Extreme cases are furnished by fanatical agitators, such as members of the Anti-Tobacco Society, in the account of whose late meeting we read that "statistics of heart-disease, of insanity, of paralysis, and the diminished bulk and stature of the population of both sexes proved, according to the report, that these diseases were attributable to the use of tobacco." But without making much of instances so glaring as this, we may find abundant proof that evidence is in most cases unconsciously distorted by the pet theories of those who give it.

Early in the history of our sanitary legislation, a leading officer of