Chapter VIII. Of Classification by Series.

§ 1. Natural groups should be arranged in a natural series 284 2. The arrangement should follow the degrees of the main phenomenon 285 3. —which implies the assumption of a type-species 287 [Pg xi]4. How the divisions of the series should be determined 288 5. Zoology affords the completest type of scientific classification 289

BOOK V. ON FALLACIES.

§ 1. Theory of fallacies a necessary part of logic 295 2. Casual mistakes are not fallacies 297 3. The moral sources of erroneous opinion, how related to the intellectual 297

§ 1. On what criteria a classification of fallacies should be grounded 301 2. The five classes of fallacies 302 3. The reference of a fallacy to one or another class is sometimes arbitrary 305