Kshatriyas, from Purusha's arm, became the warriors, as you no doubt know, if you've ever attended my gun show. Vaishyas, the merchants and artisans who provide money for the priests and the warriors, came from Purusha's thighs. Because everybody knows the thighs are the money makers and the Shudras are at the bottom. They're the feet, the laborers and the farmers, who are the foundation of the social order. Also, the rest of us stand on them. The caste system becomes much more complicated than this, but that basic division into four classes remains throughout much of Indian history. In spite of the efforts of many reformers we'll be meeting in future episodes of Crash Course, the caste system is the foundation for another big concept in Hinduism, Part Three, Dharma.