THE EXTINCT MAMMALIA. 311 



habits and then structures, especially in the soft, delicate nervous 

 tissue, the development of the function of the mind, as well as the 

 machinery of the mind, becomes perfectly possible. We develop 

 our intellect through the accumulation of exact facts ; through 

 the collation of pure truth, no matter whether it be a humble 

 kind of truth — as the knowledge of the changes of the seasons, 

 which induces some animals to lay up the winter's store ; whether 

 it be knowledge of the fact that the sting of the bee is very dis- 

 agreeable ; or knowledge of the fact (of which the wild ox, no 

 doubt, is thoroughly aware) that the teeth of the wolf are not 

 pleasant to come in contact with ; or whether it be the complex 

 knowledge of man. When the cerebral matter has become larger 

 and more complex, it receives and retains a much greater number 

 of impressions, and the animal becomes a more highly educated 

 being. 



As regards the department of emotions or passions, they are 

 also much stimulated by the environment. Animals which live in 

 a state of constant strife, naturally have their antagonistic passions 

 much developed ; while amiable, sympathetic sentiments are better 

 and more largely produced by peace-loving animals. Thus it is 

 that the various departments of the mind have the beautiful results 

 which we now find in the human species. 



There are some departments of the mind which some of our 

 friends decline to admit having had such an origin. The moral 

 faculty, for instance, is excepted by many from this series. But 

 the reasons why they object to its production in this way are, to 

 my mind, not valid. The development of the moral faculty, which 

 is essentially the sense of justice, appears to them not to fall with- 

 in the scope of a theory of descent or of evolution. It consists of 

 two parts. First is the sentiment of benevolence, or of sympathy 

 with mankind, which gives us the desire to treat them as they 

 should be treated. It is not sufficient for justice that it is un- 

 mixed mercy or benevolence, which is sometimes very injurious, 

 and very often misplaced. It requires, in the second place, the 

 criticism of the judgment, of the mature intellect, of the rational 

 faculty, to enable the possessor to dispose of his sentiments in the 

 proper manner. The combination of rational discrimination and 

 judgment, with benevolence, constitutes the sense of justice, which 

 has been derived, no doubt, as a summary of the development of 

 those two departments of the mind — the emotions and the intel- 

 lect. 



