CHAP. IX.] METHODS OF ABBREVIATION. 135 



g = things causing their work to be in a good state. 

 m= things keeping the mean in view relative to human 

 nature. 



Using, then, q as an indefinite class symbol, our premises will be 

 expressed by the following equations : 



= <?{/> (1 -/) (1 - h) +/(! -p) (l-K) + h(l -p) (1 -/)). 

 p=g(l-d). 



f=q(l-d). 

 v = qd. 



And separately eliminating from these the symbols q, 



pd = 0. (2) 



fd = 0. (3) 



v(l-d) = Q. (4) 



<7(1-7H) = 0. (5) 



Ki-^) = o. (6) 



We shall first eliminate from (2), (3), and (4) the symbol d, and 



then determine v in relation to p, /, and h. Now the addition of 

 (2), (3), and (4) gives 



From which, eliminating d in the ordinary way, we find 



0+/) = o. 



Adding this to (1), and determining v, we find 







Whence by development, 



The interpretation of this equation is : Virtue is a habit, and not 

 a faculty or a passion. 



