CLASS, CLASSIFYING, CLASSIFICA TION. When the domain of a science com prehends a very great number of objects which it is necessary to describe, or whose analogies and differences require to be assigned, It is always useful, and sometimes indispensable, to make a methodical distribution of these objects, to group those which present the great est number of common characters, to form with these groups new assemblages, continuing the process till a limit is reached where this mode of generalizing may be stopped. The highest assemblage in this ascending series is a ((class)) (though this term may not be technically ap plied to it) ; the procedure necessary in form ing it is °classifying," and the result, extending over some entire branch of natural science, is a 6classification.D We do not begin to classify till we feel the need of it, for the task requires analysis, multiplied comparisons and researches as to the means of generalizing the particular and isolated notions which we had previously been contented to amass without regular ar rangement. It is only, however, after the re vision necessary for such arrangeinent has been undertaken that science can be said to have be gun. The first attempts at generalization and classification often exercise a very important influence on the future progress of any science, and may even extend to the period when it seems to be approaching its perfection. A science consists principally in the relations of the facts observed, or knowledge acquired in connection with it. If the relations thus estab lished are founded on accurate observations, they become in fact laws of nature, the most important and most prolific truths which human reason is able to discover. But if the imagina tion has been allowed to take part in the work, if it has either furnished the materials or di rected the construction of the edifice, it must sooner or later be demolished, and rebuilt wit.h
better selected materials and on more solid foundations. In modern times geology com menced with faults of this description, and still seems to have difficulty in avoiding them. Natural history, to which a good classification is so essential, was not very fortunate in its first combinations: systems took possession of it, and too often blinded the inquirer to great truths which otherwise he could hardly have failed to discover. Influenced by this love of system, many, instead of submitting to the labo nous investigation of facts, have come forward with some new fanciful combination, and made it almost their sole business to secure the credit of their particular classifications by over throwing those of their predecessors or rivals. In a subject so comprehensive as natural history it seems vain to hope for a perfect classification until the resources of embryology are exhausted. Zoology is gradually tending toward a consist ent system of classification, the basis of which is the resemblances of animals at various periods of their growth. The impulse to this line of research was given by Darwin. Being a strictly natural method, inasmuch as the affinities by common descent are sought after to the neglect of mere outward resemblances at a later period of life, the arrangements suggested by it to dif ferent naturalists show a considerable ainount of harmony, and even those who oppose Dar win acknowledge the simplicity and consistency of embryological or genealogical classification. For the classification of the animal kingdom see ANATOMY, COMPARATIVE.