If, however, these considerations be not accepted as valid, there is another, which, to our mind, perfectly explains the absence of a remembrance of our former existences. It is, we believe, by a premeditated decree of nature, that the memory of our past lives is denied to us while we are on the earth. M. André Pezzani, the author of an excellent book called "_Pluralité des existences de l'âme_," replies to the argument of oblivion, thus: "Our terrestrial sojourn is only a new trial, as Dupont de Nemours, that wonderful writer of the eighteenth century, who outstripped all modern beliefs, has said. If this be so, can we not perceive that the remembrance of past lives would embarrass these trials by removing the greater part of their difficulties, and, in proportion, of their merit, and destroying their spontaneity? We live in a world in which free-will is all powerful, the inviolable law of the advancement and the progressive initiation of men. If past existences were known, the soul would know the meaning and the bearing of the trials reserved for it here below; indolent and idle, it would harden itself against the designs of Providence, and would be either paralyzed by its despair of overcoming them, or, if better disposed and more virile, it would accept and accomplish them unfailingly. But neither one nor the other of these positions is fitting. Our efforts must be free, voluntary, sheltered from the influences of the past; the field of strife must be seemingly untrodden, so that the athlete shall show and exercise his virtue. Previously gained experience, the energies which he has acquired, help him in the new strife, but in a latent way of which he is unconscious, for the imperfect soul undergoes these re-incarnations, in order to develop its previously manifested qualities, and to strip itself of those vices and defects which oppose themselves to the law of its ascension. What would happen if all men remembered their previous lives? The order of the earth would be overturned, or at least, it would not remain in its present condition. _Léthé_, like free-will, is a law of the world as it is."[18]