Cynicism, in its original form, refers to the beliefs of ancient school of Greek philosophers known as the Cynics. Their philosophy was that the purpose of life was to live a life of Virtue in agreement with Nature. This meant rejecting all conventional desires for wealth, power, sex, and fame, and by living a simple life free from all possessions. As reasoning creatures, people could gain happiness by rigorous training and by living in a way which was natural for humans. The first philosopher to outline these themes was Antisthenes, who had been a pupil of Socrates in the late 5th century BCE. He was followed by Diogenes of Sinope, who lived in a tub on the streets of Athens. Diogenes took Cynicism to its logical extremes, and came to be seen as the archetypal Cynic philosopher. He was followed by Crates of Thebes who gave away a large fortune so he could live a life of Cynic poverty in Athens. Cynicism spread with the rise of Imperial Rome in the 1st century, and Cynics could be found begging and preaching throughout the cities of the Empire. It finally disappeared in the late 5th century, although some have claimed that early Christianity adopted many of its ascetic and rhetorical ideas.