The 36 Tattvas [Energetic Kundalini System]

Introduction - The Darshanas
Samkhya is one of the six points of view of the classical Indian philosophical system called Darshanas. These points of views are paired so that one member of the couple is theoretical and the other one practical.
The [Vaisheshika - Nyaya] couple involves the impermanent world, or apparent and objective world. Vaisheshika involves what is specific, the scientific experimentation and Nyaya the logical reasoning.
The [Mimansa Vedanta] couple involves deep intuition and relationships between human beings, spirits and divinities. Mimansa is about the efficiency of rites that permit contacting and influencing the celestial world. Vedanta is about the universal and metaphysical aspect of reality called Brahman.
Finally, [Samkhya - Yoga] involves the permanent aspects of the world. Yoga is about introspection, or the microcosm of the inner world of the living being. Samkhya is about the nature of the universe, or of the macrocosm.
Samkhya
Samkhya appears to be one of the oldest philosophical systems of India. It includes the enumeration of the tattvas (creating principles of the world). At least two classification systems exist. The first one, classical, establishes 25 basic principles. The second one, tantric, rests upon 36 principles.
The classification presented here is that which adheres more closely to the energetic Kundalini system. Tantrism is a non-dualistic system that sees the emanation of consciousness of the Self as the non-dissociable couple formed by Shiva - Shakti (Consciousness and Energy).