theatre of the world beings who go beyond the value of a purely physical organism and of a purely somato-psychical life, and in like manner represent again a higher order of beings; just as the first appearance of organic life on earth once introduced a new and higher stage of {77} existence in contrast to the inorganic world. Scientists who take this standpoint can readily adopt the fact that we do not now observe the origination of new species; for it is in full harmony with their metaphysical doctrines, without the same being on that account essentially dependent upon the confirmation or rejection of the hypothesis of the present constancy of species. With this very fact, the maxim that if new species once originated through descent, new species must still originate through descent, has lost for them its truth, and therefore its power of demonstration. So we see even here, while in the midst of the discussion of a purely scientific problem, in what close correlation metaphysics and natural science stand, and moreover--since the metaphysical view is most closely connected with the religious--in what close relationship religion and natural science stand. At the same time we also see how little the metaphysical interest, and much more how little the religious interest, has reason to avoid the investigation of facts in nature. Sec. 4. _The Theory of Evolution--Archaeology, Ethnography, Philology._ The evolution theory teaches that the species have developed themselves one from another in gradual transitions, each of which was as small as the individual differences still observed to-day among the individuals of the same species. It is not without support, especially in the _history of the development of plants and animals_. Each organic being becomes what it is by means of organic development. Each plant, even the highest organized, begins in its seed-germ with a simple cell, {78} and is differentiated in constant development up to the fully perfected individual. Each animal, even the most highly organized (man included), begins the course of its existence as an egg; and each egg has no greater value of form than that of a single cell. This egg-cell is differentiated, after fecundation, in gradual and imperceptible transitions, farther and farther, higher and higher, until the individual has reached its perfect organization. No organ, no function of the body, no power or function of the soul or of the mind, appears suddenly, but all in gradual development. Since we see all individuals thus originating by means of gradual development, the possibility lies very near that the different organic formations of all the organic kingdoms could also have been originated by the same means.