When we study of the life of Papin, we marvel at the culture which placed him on a level with the most learned men of his times: as physician, physiologist, and mathematician, he was distinguished and honored by the universities of England and Germany. Nevertheless, what gave him his value to humanity, and hence his greatness, was the fact that his attention had been arrested by the sight of the lid of a saucepan of boiling water raised by the steam. "Steam is a force which could lift a piston as it lifts the cover of a saucepan, and become the motor power of a machine." Papin's famous saucepan is a kind of magic wand in the history of mankind, which thenceforth began to work and travel without fatigue. How wonderful are such stories of great discoveries arising from humble beginnings, and working miracles throughout the world! These, in their origins, resemble those living creatures, born of two imperceptible microscopic cells, the fusion of which inevitably tends to the creation of complex lives. To perceive exactly and to connect the things perceived logically is the work of the highest intelligence. But this work is characterized by a peculiar power of attention, which causes the mind to dwell upon a subject in a species of meditation, the characteristic mark of genius; the outcome is an internal life _rich in activities_, just as the germinative cells are the fruit of internal existences. It would seem that such mentalities are distinguished from those of the ordinary type, not by their form, but by their "force." It is the vigorous life from which those two small intellectual sparks arise, which makes them so marvelous. If they had not sprung from strong, independent personalities, capable of persistent effort and heroic self-sacrifice, those little intellectual works would have remained as things inert and negligible. Hence all that strengthens the spiritual man may lead him in the footsteps of the genius. Thus, as regards the intelligence in itself, the work it has to accomplish is a small matter, but it is clearly defined, and stripped of superfluous complications. Simplicity is the guide to discovery; simplicity which, like truth, should be naked. Very little is necessary; but this little must constitute a powerful unity; the rest is vanity. And the greater this vanity, that is to say, the futile encumbrance of the mind, the more will the light of the spirit be darkened and its forces dissipated, making it difficult or impossible not only to reason and act, but even to perceive reality, to see. * * * * * It would be interesting to make a rapid survey of those collective individual errors by which the progress of a new discovery of a simple kind, offering relief to suffering humanity, has been impeded; errors which have even caused persistent denial of the existence of obvious facts, merely because these were not generally known.