The Upanishads, part of the Vedas, explore the nature of consciousness and reality, including the concept of Brahman as the ultimate reality.

Advaita Vedanta posits that consciousness is fundamentally non-dual and universal, transcending individual differences and distinctions.

In Nyaya-Vaisheshika, Buddhi is considered the faculty of consciousness and cognition, responsible for understanding and discriminating between objects.

Atman is the term used in Indian philosophy to denote the individual self, consciousness, or soul, often associated with the concept of Brahman.

In Samkhya, Purusha is the pure consciousness or spirit that is distinct from Prakriti, the material world, and is responsible for experiencing consciousness.

Adi Shankara, a prominent Advaita Vedanta philosopher, introduced the concept of Avidya as the fundamental ignorance that leads to the illusion of separateness and the experience of suffering.

Samadhi is the ultimate goal of Yoga practice, where the mind achieves a state of complete concentration and absorption, leading to a profound experience of consciousness.

Mimamsa emphasizes the importance of Dharma, or righteous action, as the primary purpose of human consciousness and existence.

Ramanuja, a prominent Vaishnava philosopher, developed the concept of Bhedabheda, which posits that consciousness is both distinct from and inseparable from the ultimate reality, Brahman.

Charvaka, a materialist school of thought, emphasizes the importance of sensory experiences and the enjoyment of life, considering consciousness to be a product of physical processes.

Adi Shankara, a prominent Advaita Vedanta philosopher, introduced the concept of Maya, or illusion, asserting that the world we perceive is not ultimately real but a product of ignorance.

Kevala Jnana is the ultimate goal in Jain philosophy, where the soul attains perfect knowledge and liberation from karmic bondage, leading to a state of pure consciousness.

Ramanuja, a prominent Vaishnava philosopher, emphasized the significance of Bhakti, or devotion, as a path to spiritual liberation and the realization of the true nature of consciousness.

In Kashmir Shaivism, Shiva is considered the ultimate reality, encompassing all consciousness and existence, representing the dynamic and creative aspect of the universe.

Nimbarka, a prominent Vaishnava philosopher, introduced the concept of Lila, or divine play, asserting that the universe is a manifestation of the divine consciousness engaging in creative expression.