1 28 HEREDITY. 



tions are to be ranked among the disingenuous dispu- 

 tants ; nor is it conceivable that any human creature 

 could ever seriously believe that all characters and 

 actions were alike entitled to the affection and re- 

 gard of every one." (Inquiry concerning the Prin- 

 ciples of Morals, Essays, vol. ii. p. 223.) Profit a 

 man may disdain, but duty has a commanding pres- 

 ence. We can refuse to do our duty, but we are 

 unable to deny its authority over us in right. De 

 jure, conscience always rules,- although de facto it 

 may not. All languages recognize the distinction 

 between profit and duty, the desirable and the duti- 

 ful, mere expediency and the right. These great 

 phenomena in language must have a natural cause. 

 They are facts. They are hard, unmistakable, endur- 

 ing circumstances in human experience. The ques- 

 tion as to the origin of conscience is not only a vastly 

 more important one than the inquiry concerning the 

 origin of species, but it is one that can be investi- 

 gated by the scientific method almost as readily. I 

 enter on the dancing-plot of Mars here for the first 

 time. Many of you may have thought that I have 

 evaded the topic of the origin of conscience. I post- 

 poned it, in order that I might bear the whole brunt 

 of its onset, after discussing the moral sense in de- 

 tail. Having shown what conscience is, I now, with 

 some profit, I hope, may raise the question, How did 

 it originate ? 



It is evident that Darwin's hypothesis of heredi- 

 tary descent, or pangenesis, requires in the gem- 

 mules, innate powers or affinities that amount to 



