What is Man? and Other Essays - Mark Twain

"What Is Man?", published by Mark Twain in 1906, is a dialogue between a young man and an older man jaded to the world. It involves ideas of destiny and free will, as well as of psychological egoism. The Old Man asserted that the human being is merely a machine, and nothing more. The Young Man objects, and asks him to go into particulars and furnish his reasons for his position. This collection of short stories covers a wide range of Twain's interests: the serious, the political and the ironically humorous. (Summary by Wikipedia and John Greenman)