The Nyaya Philosophy is based on the oldest existing book, by Aksapada Gautama, known as the Nyaya Sutras. It is based on the theme of knowledge and logical analysis.

Nyaya Philosophy deals with knowing. It has sixteen categories, dealing with the means to understand the universe.

Nyaya Philosophy accepts the plurality of souls. Ignorance bars the way to liberation. Ignorance results from identification of the Self with the body, the sense, and the mind. Death causes rebirth because of our ignorance of the True Self. Transcendental knowledge of our True Self is Liberation, end of cycle of birth and death, and freedom from misery. Man can be liberated from the life-death cycle, only by deep logical analysis based on philosophical knowledge and dissolution of doubt and ignorance.

The most important contribution made by the Nyaya school to modern Hindu thought is its methodology, based on a system of logic.

Nyaya Philosophy is based on: Pramana -Means to acquire knowledge, Prameya - Object of knowledge, Samshaya - Doubt, Prayojana - Purpose, Drstanta - Illustrative example, Siddhanta - Conclusion, Avayava - Constituents of a syllogism, Tarka - Hypothetical argument, Nirnaya - Ascertaining the truth, Vada - Discussion, Jalpa - Disputation, Vitanda - Refutation, Hetvabhasa - Fallacy in the cause, Chala - guile, Jati - casuistry and Nigrasthana- Vulnerable point of opponent`s statement.

Early Naiyayikas( the Nyaya scholars) wrote very little about God, i.e., Ishvara. However, later Buddhists in India had become from agnostic to strictly atheistic. As a reaction, the later Naiyayikas entered into disputes with the Buddhists and tried to prove the existence of God through logic. Not only have the Naiyanikas given proofs for the existence of God, but they have also given an argument that such a God can only be one. This is discussed in the Nyaya Kusumanjali.

Therefore, Nyaya Philosophy believes in the existence of a supreme God who initiates the process of world creation.