There is not, I have already said, a city, but there is a grotto of philosophers, a natural one to which they come, and sit apart from one another or in groups, according to their schools, on chairs formed of granite blocks beside a petrifying well. This spacious grotto contains astounding stalactites, the slow product of continuous droppings which vaguely imitate, in the eyes of those who are not too critical, all kinds of beautiful objects, cups and chandeliers, cathedrals and mirrors--cups which quench no man's thirst, chandeliers which give no light, cathedrals in which no one prays, but mirrors in which one sees oneself more or less faithfully and pleasantly portrayed. There also is to be seen a gloomy and bottomless lake over which hang like so many question-marks, the pendants in the sombre roof and the beards of the thinkers. Such is the ample cave which is exactly identical to the philosophy it shelters, with its crystals sparkling amid its uncertain shadows--full of precipices, it is true. It recalls better than anything else to the new race of men, but with a still greater portion of mirage-like fascination, that diurnal miracle of our forefathers--the starry night. Now the crowd of systematic ideas which slowly form and crystallise there in each brain like mental stalactites is indescribably enormous. While all the former stalactites of thought are for ever ramifying and changing their shape, turning as it were from a table into an altar, or from an eagle into a griffin, new ideas appear here and there still more surprising. There are always, of course, Neo-Aristotelians, Neo-Kantians, Neo-Cartesians, and Neo-Pythagoricians. Let us not forget the commentators of Empedocles to whom his passion for the volcanic underworld has procured an unexpected rejuvenation of his antique authority on the minds of men, above all since an archæologist has maintained he has found the skeleton of this grand man in pushing an exploring gallery to the very foot of Ætna which to-day is completely extinct. But there is ever arising some great reformer with an unpublished gospel that each attempts to enrich with a new version destined to take its place. I will cite for example the greatest intellect of our time, the chief of the fashionable school in sociology. According to this profound thinker the social development of humanity, starting on the outer rind of the earth and continuing to-day beneath its crust, at no great distance from the surface, is destined in proportion to the growing solar and planetary cooling, to pursue its course from strata to strata down to the very centre of the earth, while the population forcibly contracts and civilisation on the contrary expands at each new descent. It is worth seeing the vigour and Dante-like precision with which he characterises the social type peculiar to each of these humanities, immured within its own circle, growing ever nobler and richer, happier and better balanced. One should