We read in the book of Ecclesiasticus: “In every good work trust thine own soul” (Ecclesiasticus xxxii. 23). Yes, let us believe in our own soul, which is the true Ego, and it will bid us live. I am far from sharing Pascal’s opinion, which is, that the Ego always merits contempt. Science, after having noted and counted the exact number of vibrations of all kinds which from all parts affect us, at a certain point ceases to have the power to calculate further, and recognises that beyond and above all vibrations there exists that which can neither be named nor counted. In my opinion that which is the best part of science is that it knows its limitations; with some people it is a well known experience that when they have once grasped the fact that their inability rightly to comprehend something they desire to know arises from an immutable decree, they become at once imbued with a profound quiescence, closely allied to certainty. After which there is but one step left to human reason, to forsake that reason which is but temporary, and to lose oneself in that which has neither beginning nor end. This last step is an act of faith. Someone, who does not think sufficiently, calls this a leap in the dark, but for him who accomplishes it this darkness becomes transparent as crystal. “Yes,” these persons exclaim, “and such was Kant’s last act.” It would be more correct to say Kant ended as he began, by an act of reason, since he drew the logical conclusion of what he had learnt. RÉSUMÉ The evolution of the human race will not become clear to us unless we remember that a time existed when man was without language and without reason. During this obscure period which we name the dawn of humanity, the material wants and their satisfaction, comprised the whole being of man, as it does that of the animal. With man commenced the line of individuals leading to the higher order of social life. It is possible that the feeling of being one of many was one of the first to awake in man, since it was owing to the support afforded him by his fellows that he obtained what he needed; he was also conscious of family ties, this emotion and sentiment was the cradle of all his best qualities; afterwards would come the attractions of race; this feeling might so dominate the individual as to cause him to forget that he was a separate entity; then by a concurrence of circumstances difficult to define, national feelings were developed from the salient features of the race, and national languages separated themselves from the central source. The knowledge of being a portion of humanity arrived at a much later period; he is still at this present time a part of a feeble few, and he can be summed up in the well-known sentence, of which the first words are, “Homo sum.” If we consider the meaning of this classical quotation it is very striking.