CONTENTS. 



Vll 



Page 



§ 2. The Predicables, what ... 81 



3. Genus and Species .... ib. 



4. Kinds have a real existence in nature 83 



5. Differentia 8C 



G. Differentiae for general purposes, acd 



differentise for special or technical 



purposes 88 



7. Proprium 89 



8. Accidens 90 



CHAPTER VIII. 



Of Definition. 

 •^ 1. Definition, why treated of in this 



place 91 



2. A definition, what . . . . (6. 



3. Every name can be defined, whose 



meaning is susceptible of analysis 92 



4. Complete, how distinguished from 



incomplete definitions . . .94 



5. — and from descriptions . . .95 

 G. What are called definitions of Things 



are definitions of Names with an 

 imphed assumption of the e.xistence 

 of Things corresponding to them . 98 



7. — even when such things do not in 



reality exist 101 



8. Definitions, though of tiames only, 



must be grounded on knowledge 

 of the corresponding Things . 103 



BOOK II. 



OF REASONING. 

 CHAPTER J. 



Of Inference, or Reasoning, in general. 

 ^ 1. Retrospect of the preceding Book . 107 



2. Inferences improperly so called . 108 



3. Inferences proper, distinguished into 



inductions and ratiocinations .111 



CHAPTER II. 



Of Ratiocination, or Syllogism. 

 § 1. Analysis of the Syllogism . .112 



2. The dictum de omui not the founda- 



tion of reasoning, but a mere iden- 

 tical proposition . . . . IIG 



3. What is the really fundamental ax- 



iom of Ratiocmation . . . 119 



4. The other form of the axiom . . 120 



CHAPTER HI. 



Of the Functions, and Logical Value, of the 



Syllogism. 

 § 1. ]s \.\ie SyWogism a petitio priricipii ? . 122 



2. Insufficiency of the common theory ih. 



3. All inference is from particulars to 



particulars 124 



4. General propositions are a record of 



such inferences, and the rules of 

 the syllogism are rules for the in- 

 terpretation of the record . . 129 



5. The syllogism not the type of rea- 



soning, but a test of it . . . 131 



6. The true type, what . . .134 



7. Relation between Induction and De- 



duction 136 



CHAPTER IV. 

 Of Trains of Reasoning, and Deductive Sciences. 

 § 1. For what purpose trains of reasoning 



exist 137 



Pago 



'J 2. A tram of reasoning is a series of 



inductive inferences . . 138 



3. — from particulars to particulars 



through marks of marks . . 139 



4. Why there are deductive sciences . 141 



5. — and why other sciences still re- 



mam experimental . . . 144 

 G. Experimental sciences may become 

 deductive by the progress of experi- 

 ment 145 



7. In what manner this usually takes 

 place 14G 



CHAPTER V. 



Of Demonstration, and Necessary Truths. 

 ^ 1. The theorems of geometry arc only 

 necessary truths in the sense of 

 necessarily following from hypoth- 

 eses 148 



2. Those hypotheses are real facts with 



some of their circumstances omit- 

 ted 150 



3. Some of the first principles of geom- 



etry are axioms, and these are not 

 hypothetical 151 



4. — but are experimental truths . . 152 



5. An objection answered . . . 154 



6. Mr. Vvhewell's opinions on axioms 



examined 155 



CHAPTER VI. 



The same Subject continued. 

 ^ 1. All deductive sciences are inductive 162 



2. The propositions of the science of 



number are not verbal, but gener- 

 alizations from experience , . 164 



3. In what sense hypothetical . . 168 



4. The characteristic property of dem- 



onstrative science is to be hypo- 

 thetical 169 



5. Definition of demonstrative evidence 



and of logical necessity . . .170 



BOOK III. 



OF INDUCTION. 



CHAPTER I. 



Preliminary Observations on Induction in general, 

 § 1. Importance of an Inductive Logic . 171 

 2. The logic of science is also that of 

 business and life .... 172 



CHAPTER II. 



Of Inductions improperly so called. 

 § 1. Inductions distinguished from verbal 



transformations .... 174 



2. — from inductions, falsely so called, 



in mathematics .... 175 



3. —and from descriptions . . . 177 



4. Examination of I\lr. Whewell's the- 



ory of induction .... 178 



CHAPTER III. 

 On the Ground of Induction. 

 5 1. Axiomofthe uniformity of the course 



of nature 183 



2. Not true in every sense. Induction 



per enumerationem simplicem . .180 



3. Tne question of Inductive Logic 



stated 187 



