(Sāṃkhya): One of six darshanas (practical visions or philosophies of orthodox Hinduism). Its emphasis is on the laws of nature, the phenomenal aspects of Universal Manifestation. The term samkhya is usually translated as “number,” “enumeration,” “calculating,” or “reasoning,” because this doctrine describes the tattvas (the different layers and degrees of manifestation), looking for their common origin in prakriti (Nature, the undifferentiated universal substance). It is believed that Samkhya was the philosophical basis for Classical Yoga. Because of its focus on the tattvas of prakriti, Samkhya was wrongly believed to be a materialistic or even atheistic system. Although its philosophy does not mention Ishvara (the Personal God), this absence (as René Guénon mentioned) is not a negation, as it is explained by the specific focus of Samkhya—which for the first time studied the intimate laws of existence, the internal processes of the material world, and the mechanisms that govern the various bodies or living organisms. In the Bhagavad Gita (5:4-5), yoga is equated to Karma Yoga and Samkhya to the path of sannyasa (renunciation), with Krishna emphasizing their essential unity.