"And to-day the globe is threaded with a network of trains drawn by flame-breathing dragons. Distances have disappeared, annihilated by improvements in the locomotive. The genius of man has contracted the dimensions of the earth; the longest voyages are but excursions over definite lines (the curved paths of the 'ocean lanes'); the most gigantic tasks are accomplished by the tireless and powerful hand of this unknown force. A telegraphic despatch flies in the twinkling of an eye from one continent to another; a man can talk with a citizen of London or St. Petersburg without getting out of his arm-chair. And these wonders attract no special notice. We little think through what struggles, bitter disappointments and persecutions they came into being! We forget that the impossible of yesterday is the accomplished fact of to-day. So it comes to pass that we still find men who come to us saying: 'Halt there, you little fellows! We don't understand you, therefore you don't know what you're talking about.' "Very well, gentlemen. However narrow may be your opinions, there is no reason for thinking that your myopia is to spread over the world. You are hereby informed that, in spite of you and in spite of your obscurantism and obstruction tactics, the car of human progress will roll on and continue its triumphal march and conquest of new forces and powers. As in the case of Galvani's frog, the laughable occurrences that you refuse to believe reveal the existence of new unknown forces. There is no effect without a cause. Man is the least known of all beings. We have learned how to measure the sun, cross the deeps of space, analyze the light of the stars, and yet have not dropped a plummet into our own souls. Man is dual,--_homo duplex_; and this double nature remains a mystery to him. We think: what is thought? No one can say. We walk: what is that organic act? No one knows. My will is an immaterial force; all the faculties of my soul are immaterial. Nevertheless, if I _will_ to move my arm, my will moves matter. How does it act? What is the mediator between mind and muscle? As yet no one can say. Tell me how the optic nerve transmits to the thinking brain the perception of outward objects. Tell me how thought is born, where it resides, what is the nature of cerebral action. Tell me--but no, gentlemen: I could question you for ten years on a stretch, and the most eminent of you could not answer the least of my interrogatories. "We have here, as in the preceding cases, the unknown element in a problem. I am far from claiming that the force that comes into play in these phenomena can one day be financially exploited, as in the case of electricity and steam. Such an idea has not the slightest interest for me. But, though differing essentially from these forces, the mysterious psychic force none the less exists.