OCR Text |
Show 84 GEOLOGY OF THE HIGH PLATEAUS. nite number of tentative classifications, having less and less of the artificial character, and approaching nearer and nearer to the natural. Each classification represents its author's coordinated knowledge of the category of which he treats, and the classifications which are generally accepted at any time represent the stage of knowledge and induction then prevailing. No system is permanent and none ought to be permanent, but they ought rather to change progressively as knowledge and induction progress. Least of all ought any system to attempt to represent anything more than we actually know. The best system at any time is that which represents most accurately the state of knowledge and rational induction at that time. The progress of classification, then, is from the simple or artificial systems which take account of one set or scale of characters and relations, to the natural systems which take into account the totality of characters and relations. Hence the classification is gradually growing more and more complex and difficult. The present conditions of most systems of classifications, viewed with reference to their respective stages of progress, seem to be much nearer the artificial than to the natural. Even in those categories of natural objects which sometimes are claimed to be classified according to natural systems, the progress from the purely artificial has often been small and the approach to the natural very distant. Though recognizing that a natural classification must embrace the totality of characters, naturalists still employ and are compelled to employ in many cases only a single set of characters for the grouping of a given category. On the other hand, we are often able to recognize correlations between the various properties or characters of a group of natural objects, such that, when we arrange them according to one set of characters, we find that we have also arranged them (in consequence of those correlations) in logical harmony with the others. But this rarely happens except in very small groups with a narrow range of variation; our knowledge is rarely equal to a full and sufficient recognition of such correlations in large groups. Most of the later classifications, however, assume the existence of such correlations while using a single character as a criterion. Although this course is far from being wholly satisfactory, it appears to be the only practicable one. Sometimes this assumption holds true to a remarkable extent; much more frequently the |