define four noble truths
The Four Noble Truths are regarded as the central doctrine of the Buddhist tradition, and are said to provide a conceptual framework for all of Buddhist thought. These four truths explain the nature of dukkha, its causes, its cessation, and the path leading to its cessation.
The system of the four classes (caturvarnya) is fundamental to the views the traditional lawgivers held of society. They specified a different set of obligations for each: the task of the Brahman is to study and advise, the baron to protect, the Vaishya to cultivate, and the serf to serve.