In science, therefore, there is much free expression; but beauty not yet. No abstract expression such as Euclid's _Elements_, Newton's _Principia_, or Peano's _Formulaire_, no matter how rigorous and complete, is a work of art. We admire the mathematician's formula for its simplicity and adequacy; we take delight in its clarity and scope, in the ease with which it enables the mind to master a thousand more special truths, but we do not find it beautiful. Equally removed from the sphere of the beautiful are representations or descriptions of mere things, whether inaccurate or haphazard, as we make them in daily life, or accurate and careful as they are elaborated in the empirical sciences. No matter how exact and complete, the botanist's or zoologist's descriptions of plant and animal life are not works of art. They may be satisfactory as knowledge, but they are not beautiful. There is an important difference between a poet's description of a flower and a botanist's, or between an artistic sketch and a photograph, conferring beauty upon the former, and withholding it from the latter. The central difference is this. The former are descriptions not of things only, but of the artist's reactions to things, his mood or emotion in their presence. They are expressions of total, concrete experiences, which include the self of the observer as well as the things he observes. Scientific descriptions, on the other hand, render objects only; the feelings of the observer toward them are carefully excluded. Science is intentionally objective,--from the point of view of the artistic temperament, dry and cold. Even the realistic novel and play, while seeking to present a faithful picture of human life and to eliminate all private comment and emotion, cannot dispense with the elementary dramatic feelings of sympathy, suspense, and wonder. sthetic expression is always integral, embodying a total state of mind, the core of which is some feeling; scientific expression is fragmentary or abstract, limiting itself to thought. Art, no less than science, may contain truthful images of things and abstract ideas, but never these alone; it always includes their life, their feeling tones, or values. Because philosophy admits this element of personality, it is nearer to art than science is. Yet some men of science, like James and Huxley, have made literature out of science because they could not help putting into their writings something of their passionate interest in the things they discovered and described.