FALLACIES OF CONFUSION. 463 



as a serious argument, but as a criticism on what he 

 deemed an inappropriate expression. " Rem ipsam 

 prorsus probo : elegantiam desidero. Appellet hsec 

 desideria nature ; cupiditatis nomen servet alio," &c. 

 But many persons, both ancient and modern, have 

 employed this, or something equivalent to it, as a real 

 and conclusive argument. We may remark that the 

 passage respecting cupiditas and cupidus is also an 

 example of another fallacy already noticed, that of 

 Paronymous Terms. 



Many more of the arguments of the ancient 

 moralists, and especially of the Stoics, fall within the 

 definition of Petitio Principii. In the De Finibus, for 

 example, which I continue to quote as being probably 

 the best extant exemplification at once of the doctrines 

 and the methods of the schools of Greek philosophy 

 existing at that time; what are we to think of the 

 arguments of Cato in the third book, derived from 

 common notions : That if virtue were not happiness, 

 it could not be a thing to boast of: That if death or 

 pain were evils, it would be impossible not to fear 

 them, and it could not, therefore, be laudable to 

 despise them, &c. In one way of viewing these argu- 

 ments, they may be regarded as appeals to the 

 authority of the general sentiment of mankind, which 

 had stamped its approval upon certain actions and 

 characters by the phrases referred to ; but that such 

 could have been the meaning intended is very un- 

 likely, considering the contempt of the ancient philo- 

 sophers for vulgar opinion. In any other sense they 

 are clear cases of Petitio Principii, since the word 

 laudable, and the idea of boasting, imply principles of 

 conduct ; and practical maxims can only be proved 

 from speculative truths, namely, from the properties 

 of the subject matter, and cannot, therefore, be em- 



