So the sap in its evolution took the common way of all life's forces. It rose towards its highest forms, in turn becoming leaf and flower and fruit: and then it fell away in hard, dry, woodenish particles. Through this history of changing shape passes all we know, ideas as well as things. Even our feelings are not exempt. Everything within and without us alters and re-forms itself: so that there is no changeless situation, nothing which is for ever exactly the same. In the indestructible and turbulent race of matter one universal essence is working in a fixed direction: and if the tree-sap changed into wood, after having triumphally been green leaf and shining flower, so does implacable fate lead our component cells through exquisite childhood into splendid youth, only to change us at last into tottering and wasted creatures of old age. The elements alter their shape through time and space. In the same light, in the same conditions and circumstances, flowers bloom and fade, our hair turns from its first dark or fair colour into silver, our eyes lose their early fire, our firm red flesh goes dry and shrivelled. These changes happen to the same drop of sap in the plant world, and to the same tissue in the animal world. In the unexplored world of instinct our senses follow a similar evolution. Our enthusiasm for something or other springs to life, lasts awhile, and then chills into complete detachment. "Love is akin to hate," says a proverb: but really the two states run together. Our indifference or our dislike is often born of an exhausted regard: otherwise would we so often come to hate what we once enjoyed? No, these rising and falling changes are not confined to plants, but are a general part of evolution, in material as in immaterial things. Springtime, however, with its thrill towards active life prevailed once again upon the earth. The sap was boiling up in the inmost pores of the giant tree. It was shaken in mysterious travail, sharing, in its tree-fashion, the corresponding sensations of living beings: but expressing them of course very differently. Its passionate re-birth was shown in the perfumes which it released, in the trembling of its branches, in its needles flashing silver in the moonlight, or golden in the full light of the sun. Yet these enigmatical eddies were those of the new year, the same which make our blood hot and our desires keen.