Page:Popular Science Monthly Volume 71.djvu/513

Rh in its details—Linnæus began that theoretical reduction of the several parts of a plant to modifications, under special conditions, of a few simple organs, which Goethe was to elaborate and carry much farther in his "Metamorphose der Pflanzen" (1790). Goethe makes due acknowledgment of his debt to Linnæus (who was his constant study in his early years ) in that treatise, the place of which in the history of botany is well known. Contemporary botanists would, I suppose, incline to question whether this theory has done greater service or harm to the progress of their science. Its chief value lay in its tendency to suggest the idea of the unity of type—and eventually the idea of the common derivation through processes of transformation—of different species. Both of these ideas were far from the mind of Linnæus; with him the theory took the form only of the purely specific doctrine of the interchangeability of leaf and flower under varying conditions of nourishment, or at different phases of the individual plant's growth.

In these two instances, then, Linnæus made some contribution to the unification, as well as to the augmentation, of knowledge. Yet his lack of any penetrating insight into the larger relations of biological facts and the absence in him of any sound grasp of scientific method, disqualified him from taking a place among those who have materially enriched our stock of the ideas and categories which may be used in the interpretation of nature. His emphasis upon the static aspects of the world of living organisms—upon the fixed characters of species—and upon the descriptive rather than explanatory business of scientific inquiry made his influence, on the whole, an obstacle to the development and diffusion of those evolutional ideas which were already stirring in a number of minds of his generation. His ineptitude in the more philosophic part of the naturalist's work could not be better shown than in the one treatise in which he attempts a broad philosophical view and a wide correlation of organic phenomena. This writing, "Œconomia Naturæ," which was greatly admired by his contemporaries, points out in how diverse and complicated ways organisms of different species interact with one another, and are reciprocally adapted to one another, as well as to the conditions of survival in their environment. In dilating upon this Linnæus may be said to call attention, more than a century before Darwin, to the reality and importance in nature of the struggle for existence between species; for he shows how every kind of organism has its natural enemies, with which it keeps up