The Upanishads are a collection of philosophical texts that form the core of Hindu philosophy. They explore fundamental questions of existence, reality, and the nature of the self.

Gautama Akshapada, also known as Gotama, is credited with developing the Nyaya system of logic and epistemology, which significantly influenced Indian and Buddhist thought.

The concept of anatta or anatman is a fundamental teaching in Buddhism, asserting that there is no permanent, unchanging self or soul.

Kapila, the founder of the Samkhya school of philosophy, introduced the concept of gunas to explain the nature of reality and the interactions between matter and consciousness.

Ahimsa is a fundamental tenet of Jainism, emphasizing the avoidance of violence and harm to all living beings.

Shankara, the founder of the Advaita Vedanta school, propounded the concept of maya, asserting that the phenomenal world is an illusion and only Brahman, the ultimate reality, is true.

The concept of karma is deeply ingrained in Hindu philosophy, emphasizing the moral consequences of one's actions and the cycle of rebirth.

Ramanuja, a prominent philosopher in the Vaishnava tradition, rejected the concept of maya and asserted the existence of a personal God, Vishnu, as the ultimate reality.

The concept of moksha is a fundamental aspiration in Hinduism, Buddhism, Jainism, and Sikhism, representing the ultimate goal of liberation from suffering and the cycle of rebirth.

Mahavira, the founder of Jainism, propounded the theory of anekantavada, asserting that truth is multifaceted and can be viewed from different perspectives.

The concept of dharma is a fundamental ethical principle in Hinduism, Buddhism, Jainism, and Sikhism, emphasizing the importance of righteous conduct, moral duty, and social harmony.

Krishna, in the Bhagavad Gita, expounded the concept of svadharma, urging individuals to fulfill their duties and obligations according to their social and spiritual roles.

The concept of nirvana is a fundamental goal in Buddhism, representing the ultimate state of liberation from suffering and the cycle of rebirth.

Nagarjuna, a prominent philosopher in the Madhyamaka school of Buddhism, propounded the theory of sunyata, asserting that all phenomena are empty of inherent existence.

The concept of brahman is a fundamental metaphysical principle in Hinduism, representing the ultimate reality, the source of all existence, and the ground of all being.