How does it happen that in spite of such unfavourable circumstances, often with no clear purpose, and with eyes half shut, humanity can advance? For the progress is indubitable. The public conscience has developed; and its actions make themselves felt; civilised nations have become more humane; they understand better than they did formerly that peace is more profitable than war; certain social problems are being seriously discussed, and some are on the point of solution. In the physical sciences, as well as in mechanical arts, progress is most marked. But I see that though imagination, observation, and a talent for invention have had much to do with this progress, the capacity of imitation has also been a powerful factor. When William Herschel gave up music for astronomy, he perfected the optical instruments which were in use at that time, and manufactured some excellent telescopes at comparatively moderate prices, with the result that his fellow astronomers and their successors were able to devote themselves to the study of the heavens with greater ease and readiness; and the discovery of Uranus was soon followed by that of a large number of celestial bodies. Again, at one of the National Exhibitions of our time, there was shown to all comers the model of a recently invented apparatus for the conveyance of the wounded on battlefields; since which, each country now produces its own design with various improvements, and the victims of the barbarism, still lingering in war, were benefited by these modern appliances, due entirely to the art of imitation. In short, progress exists, but not all along the line. As thought travels slowly in its own domain, so mental science is behindhand. A true idea is not mechanically reproduced, it must be tended for it to bear fruit, but what tendance would avail, if it is only with difficulty that we discriminate between what we know already, and what we do not yet know, for this distinction must accompany conscious progress. Everything around us tends to keep us in this penumbra, which is so favourable to inertia, ignorance, sleep. Certain groups of philosophical ideas become condensed and systematised; in some systems there are one or two great thoughts only. This suffices--these systems remain, germinate and direct contemporaneous generations as well as those of the future. It may also happen that these same ideas invade brains little prepared to receive them, and thus deviate from their course, err as they advance, and end by becoming so travestied that it is no longer possible to know what they were at their origin--a swerving movement has taken place, which causes suffering to contemporaries, and, still more, to those who come after. Thus the bulk increases, the bulk of truth and the bulk of error; and this fatal expansion of the true and the false, intertwined the one with the other, pursues its encroaching and troublous way.