But now the roles are reversed; tradition descends from the upper to the lower ranks, while Reason ascends from the latter to the former. —­ On the one hand religion and monarchy, through their excesses and misdeeds under Louis XIV, and their laxity and incompetence under Louis XV, demolish piece by piece the basis of hereditary reverence and filial obedience so long serving them as a foundation, and which maintained them aloft above all dispute and free of investigation; hence the authority of tradition insensibly declines and disappears.  On the other hand science, through its imposing and multiplied discoveries, erects piece by piece a basis of universal trust and deference, raising itself up from an interesting subject of curiosity to the rank of a public power; hence the authority of Reason augments and occupies its place. —­ A time comes when, the latter authority having dispossessed the former, the fundamental ideas tradition had reserved to itself fall into the grasp of Reason.  Investigation penetrates into the forbidden sanctuary.  Instead of deference there is verification, and religion, the state, the law, custom, all the organs, in short, of moral and practical life, become subject to analysis, to be preserved, restored or replaced, according to the prescriptions of the new doctrine.

II.  Ancestral tradition and culture.

Origin, nature and value of hereditary prejudice. — How far custom, religion and government are legitimate.

Nothing could be better had the new doctrine been complete, and if Reason, instructed by history, had become critical, and therefore qualified to comprehend the rival she replaced.  For then, instead of regarding her as an usurper to be repelled she would have recognized in her an elder sister whose part must be left to her.  Hereditary prejudice is a sort of Reason operating unconsciously.  It has claims as well as reason, but it is unable to present these; instead of advancing those that are authentic it puts forth the doubtful ones.  Its archives are buried; to exhume these it is necessary to make researches of which it is incapable; nevertheless they exist, and history at the present day is bringing them to light. —­ Careful investigations shows that, like science, it issues from a long accumulation of experiences; a people, after a multitude of gropings and efforts, has discovered that a certain way of living and thinking is the only one adapted to its situation, the most practical and the most salutary, the system or dogma now seeming arbitrary to us being at first a confirmed expedient of public safety.  Frequently it is so still; in any event, in its leading features it is indispensable; it may be stated with certainty that, if the leading prejudices of the community should suddenly disappear, Man, deprived of the precious legacy transmitted to him by the wisdom of ages, would at once fall back into a savage condition and again