LOGIC 309 



But Napoleon I. violated his engagements to 



the Republic to make himself supreme. 

 Therefore Napoleon I. was a tyrant. 

 All tyrants are unjust. 

 Napoleon I. was a tyrant. 

 Therefore Napoleon I. was unjust. 



Syllogisms may also be hypothetical instead of cate- 

 gorical, and hypothetical syllogisms may be conditional 

 or disjunctive. 



The following is their form : 



(1) Conditional: 



If A is B then C is D. 

 (Antecedent) (Consequent) 

 or if A is B then A is C 



but A is B therefore A is C. 



or finally if A is B then A is C. 

 but if A is D then A is B. 



therefore if A is D then A is C 



(2) Disjunctive syllogisms are thus expressed : 

 either A is B or C is D. 



or either A is B or A is C. 



A dilemma is a particular form of " disjunctive " syl- 

 logism, e.g., 



If A is B then either C is D or E is F. 

 but neither C is D nor E is F. 

 therefore A is not B. 



Induction * does not depend on the syllogistic principle, 

 but on a belief in the order and continuity of nature. 



* See ante, pp. 260 and 294. 



