The Samkhya Philosophy or the school of enumeration is also known as Sankhya, the Sanskrit meaning of which is enumeration. It is one of the 6 schools of Indian orthodox philosophy and is believed that sage Kapila was the original founder of this school of philosophy. The Samkhya Philosophy was one of the earliest Indian attempts towards a systematic philosophy. Samkhya has two schools of philosophy - the theist school and the atheist school of philosophy. Though presently there are no purely Samkhya schools existing in Hinduism, yet its influence is felt in Yoga and Vedanta schools.

Etymology of Samkhya Philosophy
The word Samkhya is composed of 2 words sain, which means "correct or proper" and khya means "all knowing". In the context of ancient Indian philosophies, Samkhya refers to the philosophical school in Hinduism based on systematic enumeration and rational examination.

History of Samkhya Philosophy
Samkhya philosophy emerged as a distinct school of philosophy between the 5th and 2nd century BCE. It has been named so as it enumerates 25 true principles, also called Tattvas, and focuses on emancipation of 25th Tattva which is Purusha or soul. Philosophical texts belonging to this era have references to Samkhyan concepts and terminologies. It has been concluded that around 2000 years ago Samkhya philosophy became the representative philosophy of Hindu thought and extensively influenced Hindu texts and traditions.

Objective of Samkhya Philosophy
The object of Samkhya is to show how the final emancipation of the soul from the bondage of pain is to be effected. An attempt is made to set forth the cause of this universal bondage. According to the Samkhya system, souls are innumerable, immaterial, unmixed, all-pervading and inactive. The Samkhya philosophy does not recognize God`s existence. The Sankhya system discriminates between a subtle body and a gross body. The Sankhya system is called by the name of Mrishwar or godless. Yet it is an offshoot of a system of superstition. Samkhya, like all other systems of Indian philosophy, regards ignorance as the root cause of bondage and suffering. It emphasises on the fact that a pure mind is essential to make living in this universe worthwhile. Unless human mind gets rid of all gross elements it is not possible to achieve a state of eternal bliss.

Principles of Samkhya Philosophy
Samkhya philosophy regards the universe as consisting of two eternal realities: Purusha and Prakriti. Purusha is the centre of consciousness, whereas, Prakriti is the source of all material existence. Samkhya forms the philosophical basis for Yoga of Patanjali as well. The Samkhya system proposes the theory of evolution that is accepted by all other systems. Hence the Samkhya system is based on dualism wherein nature and conscious spirit are separate entities not derived from one another. Samkhya is essentially atheistic because it believes that the existence of God cannot be proved. Generally, the Samkhya system classifies all objects as falling under one of the two categories: Purusha and Prakriti. Metaphysically, Samkhya maintains a revolutionary duality between spirit and matter.

Theory of Causation in Samkhya Philosophy
The Samkhya Theory of Causation is known as Satkaryavada, according to which the effect exists in its cause prior to its production. The basic philosophy of this particular theory asks whether the effects pre-exist in its material state. To this, who answer in negative is known as Asatkaryavadins and the others who give their answer in affirmative are known as Satkaryavadins. In this Theory of Causation the concept of samogya was added later, which literally meant the permutation and combination of the various elements. Each combination and permutation produces a different result and in Samkhya, the concept of samyoga is explained in detail in the Theory of Manifestation.

Dualism in Samkhya Philosophy
The Samkhya School of Philosophy says that the Purusha is an unrelated element and a state of pure consciousness which presides over every individual mind. According to the Samkhya philosophy, the Prakriti is the original matter and is composed of the three Gunas composed with the elements of truth and virtue. The Samkhya philosophy states that when an individual does not have the realisation of the true state of Purusha, he is easily misled by the physical entity or the Prakriti.

The two entities of existence are of prime importance according to the Samkhya philosophy. It emphasises on the single existence of the Prakriti and says that the Purusha has multiple entities. The philosophy of Samkhya is based on Satkaryavada. According to Satkaryavada, the effect already exists in the cause. Cause and effect are considered as temporal aspects of the same thing.

Influences of Samkhya Philosophy
Samkhya philosophy has also influenced many ancient theories of soul in Vedic as well as non Vedic souls. The mention of the ideas developed under Samkhya philosophy has been found in the early Hindu scriptures like Bhagavad Gita, Upanishads and Vedas. The Indra-Vritra myth of Rig Veda, compiled in second millennium BCE, has also the mention of dualism. The hymns of Purusha sukta and the emphasis of duality in the Nasadiya sukta of Rig Veda also have been influenced by the philosophy. Hymns of the Atharvaveda also mention the concept of Purusha. Major Upanishads written in 900-600 BCE also has speculations similar to the classical Samkhya philosophy. The concept of ahamkara has been illuminated in Chandogya Upanishad and Brhadaranyaka Upanishad. The idea of pure consciousness was developed by Upanishadic sages, Yajnavalkya and Uddalaka Aruni. Samkhya also has enumeration of tattvas which can also be traced in Taittiriya Upanishad, Brihadaranyaka Upanishad and Aitareya Upanishad. Samkhya philosophy has also influenced Buddhist and Jain concepts.