gates will remain the same under similar conditions. This conception, so self-evident to-day, was slow to dawn upon the human mind. Ancient pagan belief, various forms of superstition, as well as theology, all assumed life to be under the special control of a mysterious and arbitrary power. The conviction that it is subject to laws, as unalterable as those that govern the physical universe, has only gained ground within a comparatively recent period. Nor could such a view assert itself until mathematics and statistics had reached a certain degree of perfection; for, previous to that, the law of averages and probabilities, as applicable to social problems, could not be understood.
Even after science had taken the initiative, and formulated the law upon such data as were accessible, a long period elapsed before steps were taken to apply its principles to practical ends. The conditions of society were as yet too unsettled, property and life too insecure, to permit such experiments. Not until after the middle of the eighteenth century did the desire to provide for widows, orphans, and other dependents, become so general as to lead to the establishment of a life-insurance society in London.
Since then the system has been steadily perfected, and has grown to considerable dimensions all over the civilized world. At present more than 600,000 lives are insured in the United States alone; and the usefulness of the institution is only beginning to be properly appreciated. In view of this fact, and of the general interest that cooperative enterprises are attracting just now, it may be well to point out that life insurance must be reckoned among the grandest and most successful efforts ever attempted in that direction. It has, moreover, a century's experience to attest the strictly scientific principles upon which it rests. Such an institution well deserves to be better and more generally understood; but, however large the number directly interested, it is strange how few have correct notions about it. This is probably attributable to the character of the literature on the subject, which, addressed to specialists, employs many technical terms, or, intended for soliciting agents, contains mere platitudes. Thus the impression prevails that it is either too dry or veiled in too much mystery to deserve the attention of even the educated classes.
It will be the aim of these articles, while giving an outline of the origin and history of mortality-tables, the results attained, and an explanation of the practical working of the whole system, to present it in so plain and popular a manner as to be readily understood by every intelligent reader.
I. Origin and History.—Among the nations of antiquity, the Romans were the first to make an effort to arrive at a law of mortality. To this they were led indirectly by their highly developed system of jurisprudence. It became necessary at times to fix the value of life-estates, i. e., property owned during lifetime only, without the right of alienation or bequest, and to do so the probability of life had to be
