This is an EXACT reproduction of a book published before 1923. This IS NOT an OCR'd book with strange characters, introduced typographical errors, and jumbled words. This book may have occasional imperfections such as missing or blurred pages, poor pictures, errant marks, etc. that were either part of the original artifact, or were introduced by the scanning process. We believe this work is culturally important, and despite the imperfections, have elected to bring it back into print as part of our (...) continuing commitment to the preservation of printed works worldwide. We appreciate your understanding of the imperfections in the preservation process, and hope you enjoy this valuable book. (shrink)

The species concept is one of the oldest and most fundamental in biology. And yet it is almost universally conceded that no satisfactory definition of what constitutes a species has ever been proposed. The present article is devoted to an attempt to review the status of the problem from a methodological point of view. Since the species is one of the many taxonomic categories, the question of the nature of these categories in general needs to be entered into.

The aim of this paper is on the one hand to remind the Western reader of some aporias of Chinese antiquity, and on the other hand to show that a logic of sorts or of types similar to that which has been proposed to explain the relation between categories (in the mathematical sense of the term) and logic brings much light on these aporias. This should be contrasted with older traditional explanations using conventional syllogistics or feeling satised with too simple (...) explanations such as the confusion between inclusion and identity. The article is based on preceding papers of the Author, but stresses the basic unity of the solutions which were proposed there. (shrink)