CONTENTS. 



CHAPTER VI. 



THE INDIRECT METHOD OF INFERENCE. 

 SECTION PARE 



1. The Indirect Method of Inference 81 



2. Simple Illustrations 83 



3. Employment of the Contrapositive Proposition 84 



4. Contrapositive of a Simple Identity 86 



5. Miscellaneous Examples of the Method 88 



6. Mr. Venn's Problem 90 



7. Abbreviation of the Process 91 



8. The Logical Alphabet 94 



9. The Logical Slate 95 



10. Abstraction of Indifferent Circumstances 97 



11. Illustrations of the Indirect Method 98 



- 12. Second Example 99 



13. Third Example 100 



14. Fourth Example 101 



15. Fifth Example 101 



16. Fallacies Analysed by the Indirect Method 102 



17. The Logical Abacus ,104 



18. The Logical Machine 107 



19. The Order of Premises 114 



20. The Equivalence of Propositions 115 



21. The Nature of Inference . . 118 



CHAPTER VII. 



INDUCTION. 



1. Induction ,121 



2. Induction an Inverse Operation 122 



3. Inductive Problems for Solution by the Reader 123 



4. Induction of Simple Identities 127 



5. Induction of Partial Identities 130 



6. Solution of the Inverse or Inductive Problem, involving Two 



Classes 134 



7. The Inverse Logical Problem, involving Three Classes . . . 137 



8. Professor Clifford on the Types of Compound Statement in- 



volving Four Classes 143 



9. Distinction between Perfect and Imperfect Induction . . . 146 

 10. Transition from Perfect to Imperfect Induction 149 



