ABSTRACT
The conservative true believers, however, were not destined to hold the field entirely to themselves. Around the middle of the first millennium bce, various alternative philosophies began to develop into popular movements, often styled as "reform" movements. Buddhism and Jainism are two of the better-known reform movements that developed during that time. The orthodox darshanas, six in number, supported and attempted to rationally defend the truth of the shruti tradition. The heterodox darshanas offered new, and in some cases, radically new alternatives. This chapter examines the principle darshanas in both the orthodox and the heterodox groups. During the era that followed the Age of the Upanishads, the Hindu tradition came to recognize six orthodox darshanas. The chapter begins with Purva Mimamsa because it is the most solidly fundamentalist of the orthodox group. Both Samkhya and Yoga darshanas are closely associated with Vedanta, and over time, many elements of both became integrated into the broader nature of Vedanta.
