are upheld by a deliberate public opinion as to what is right and seemly. In the popular apprehension, and indeed in the apprehension of the trained jurists and scholars for the time being, these constituent principles of the accepted point of view are "fundamentally and eternally right and good." But this perpetuity with which they so are habitually invested in the popular apprehension, in their time, is evidently such a qualified perpetuity only as belongs to any settled outgrowth of use and wont. They are of an institutional character and they are endowed with that degree of perpetuity only that belongs to any institution. So soon as a marked change of circumstances comes on, -- a change of a sufficiently profound, enduring and comprehensive character, such as persistently to cross or to go beyond those lines of use and wont out of which these settled principles have emerged, -- then these principles and their standards of validity and finality must presently undergo a revision, such as to bring on a new balance of principles, embodying the habits of thought enforced by a new situation, and expressing itself in a revised scheme of authoritative use and wont, law and custom. In the transition from the medieval to the modern point of view, e. g., there is to be seen such a pervasive change in men's habitual outlook, answering to the compulsion of a new range of circumstances which then came to condition the daily life of the peoples of Christendom. In this mutation of the habitual outlook, between medieval and modern times, the contrast is perhaps most neatly shown in the altered standards of knowledge and belief, rather than in the settled domain of law and morals. Not that the mutation of habits which then overtook the Western world need have been less wide or less effectual in matters of conduct; but the change which has taken effect in science and philosophy, between the fourteenth century and the nineteenth, e. g., appears to have been of a more recognizable character, more easily defined in succinct and convincing terms.
It has also quite generally attracted the attention of those men who have interested themselves in the course of historical events, and it has therefore become something of a commonplace in any standard historical survey of modern civilisation to say that the scheme of knowledge and belief underwent a visible change between the Middle Ages and modern times.
It will also be found true that the canons of knowledge and belief, the principles governing what is fact and what is credible, are more intimately and intrinsically involved in the habitual behavior of the human spirit than any factors of human habit in other bearings. Such is necessarily the case, because the principles which guide and limit knowledge and belief are the ways and means by which men take stock of what is to be done and by which they take thought of how it is to be done. It is by the use of their habitual canons of knowledge and belief, that men construct those canons of conduct which serve as guide and standards in practical life. Men do not pass appraisal on matters which lie beyond the reach of their knowledge and belief, nor do they formulate rules to govern the game of life beyond that limit.
So, congenitally blind persons do not build color schemes; nor will a man without an "ear for music" become a master of musical composition. So also, "the medieval mind" took no thought and made no provision for those later-arisen exigencies of life and those later-known facts of material science which lay yet beyond the bounds of its medieval knowledge and belief; but this "medieval mind" at the same time spent much thought and took many excellent precautions about things which have now come to be accounted altogether fanciful, -- things which the maturer insight, or perhaps the less fertile conceit, of a more experienced age has disowned as being palpably not in accord with fact.
That is to say, things which once were convincingly substantial and demonstrable, according to the best knowledge and belief of the medieval mind, can now no longer be discerned as facts, according to those canons of knowledge and belief that are now doing duty among modern men as conclusive standards of reality. Not that all persons who are born within modern times are thereby rendered unable to know and to believe in such medieval facts, e. g., as horoscopes, or witchcraft, or gentle birth, or the efficacy of prayer, or the divine right of kings; but, taken by and large, and in so far as it falls under the control of the modern point of view, the deliberate consensus of knowledge and belief now runs to the effect that these and other imponderables like them no longer belong among ascertained or ascertainable facts; but that they are on the other hand wholly illusory conceits, traceable to a mistaken point of view prevalent in that earlier and cruder age.
The principles governing knowledge and belief at any given time are primary and pervasive, beyond any others, in that they underlie all human deliberation and comprise the necessary elements of all human logic. But it is also to be noted that these canons of knowledge and belief are more immediately exposed to revision and correction by experience than the principles of law and morals. So soon as the conditions of life shift and change in any appreciable degree, experience will enforce a revision of the habitual standards of actuality and credibility, because of the habitual and increasingly obvious failure of what has before habitually been regarded as an ascertained fact.
Things which, under the ancient canons of knowledge, have habitually been regarded as known facts, -- as, e. g., witchcraft or the action of bodies at a distance, -- will under altered circumstances prove themselves by experience to have only a supposititious reality.
Any knowledge that runs in such out-worn terms turns out to be futile, misleading, meaningless; and the habit of imputing qualities and behavior of this kind to everyday facts will then fall into disuse, progressively as experience continues to bring home the futility of all that kind of imputation. And presently the habit of perceiving that class of qualities and behavior in the known facts is therefore gradually lost. So also, in due time the observances and the precautions and provisions embodied in law and custom for the preservation or the control of these lost imponderables will also fall into disuse and disappear out of the scheme of institutions, by way of becoming dead letter or by abrogation. Particularly will such a loss of belief and insight, and the consequent loss of those imponderables whose ground has thereby gone out from under them, take effect with the passing of generations.
An Imponderable is an article of make-believe which has become axiomatic by force of settled habit. It can accordingly cease to be an Imponderable by a course of unsettling habit.
Those elders in whom the ancient habits of faith and insight have been ingrained, and in whose knowledge and belief the imponderables in question have therefore had a vital reality, will presently fall away; and the new generation whose experience has run on other lines are in a fair way to lose these articles of faith and in. sight, by disuse. It is a case of obsolescence by habitual disuse. And the habitual disuse which so allows the ancient canons of knowledge and belief to fall away, and which thereby cuts the ground from under the traditional system of law and custom, is re-enforced by the advancing discipline of a new order of experience, which exacts an habitual apprehension of workday facts in terms of a different kind and thereby brings on a revaluation and revision of the traditional rules governing human relations. The new terms of workday knowledge and belief, which do not conform to the ancient canons, go to enforce and stabilise new canons and standards, of a character alien to the traditional point of view. It is, in other words, a case of obsolescence by displacement as well as by habitual disuse.
This unsettling discipline that is brought to bear by workday experience is chiefly and most immediately the discipline exercised by the material conditions of life, the exigencies that beset men in their everyday dealings with the material means of life; inasmuch as these material facts are insistent and uncompromising. And the scope and method of knowledge and belief which is forced on men in their everyday material concerns will unavoidably, by habitual use, extend to other matters as well; so as also to affect the scope and method of knowledge and belief in all that concerns those imponderable facts which lie outside the immediate range of material experience. It results that, the further course of in changing habituation, those imponderable relations, conventions, claims and perquisites, that make up the time-worn system of law and custom will unavoidably also be brought under review and will be revised and reorganised in the light of the same new principles of validity that are found to be sufficient in dealing with material facts.
Given time and a sufficiently exacting run of experience, and
