PREFACE 



LUCILIUS, my much esteemed friend While a great i 

 gulf separates philosophy from the other learned 

 arts, there is to my mind an equally wide gulf in 

 philosophy itself between the portion which relates 

 to human conduct and that which deals with the 

 nature and power of heaven. The latter is more 

 exalted and more speculative, it allows itself wide 

 liberty. It is not satisfied with mere observation, 

 it surmises that there is a greater and fairer realm 

 placed by nature beyond human sight. Between 

 these two divisions of philosophy, in short, there is 

 as wide a gulf as between their subjects, God and 

 man. 



The one teaches us what should be done 2 

 on earth ; l the other, what is done in heaven. 

 The one dispels our errors and flashes a light by 

 which to thread the mazes of life ; the other far 

 transcends this gloom. in which we grope, rescues 

 us from the darkness, and leads us to the very 

 source of light itself. For myself, I am grate- 

 ful to nature, not so much when I see her on the 

 side that is open to the world, as when I am per- 

 mitted to enter her shrine. Then one may seek to 

 know of what stuff the universe is made, who is its 

 author or guardian, what is the nature of God. Is 



1 In other words, the principles of human conduct. 

 3 



