Saiva Siddhantha developed as a philosophy in the Tamil community and is based both on the Vedas and Agamas. Its literature mainly consists of seven major books. (i) Twenty- eight Saivite Agamas, (ii) Saivites hymns called Thirumurai, (iii) Thirumandiram, (iv) Periyapuranam, (v) Sri Meykandar's Sivajnana- Bodham, (vi) Sri Arulnandhi's Sivajnana Siddhiar and (vii) the works of Sri Umapathi. Its philosophy stands between Sankara's Advaitha and Ramanuja's Bhakthi system. According to this doctrine, a form of monistic Theism, the supreme reality is Siva. He is Omnipotent, Omnipresent, Omniscient, changeless, eternal, free and perfect. He is Immanent and Transcendent. Above all He is Love, the only quality we can comprehend. His infinite love reveals itself through the five divine acts of creation, preservation and destruction of the universe according to the laws of Karma, the veiling or obscuration and liberation of souls through His Grace. Sri Siva pervades the whole world by His Sakthi. Sakthi is the conscious energy of Siva. She is the very body of Siva. While He is pure conscious and the universe is pure unconscious, Sakthi is the link between them. Sakthi is the material cause of the universe.

The universe, which undergoes evolution for the benefit of the souls, is real and eternal. The world of matter and the soul are different from the Body of the Lord. Souls, in their nature, are infinite, eternal and omniscient like God; but, they imagine themselves to be finite, temporary and ignorant. This is because they are in bonds. To obtain salvation, we must get rid of these three bonds of Aanava, Karma and Maya. All these can be obtained by self discipline, the help of a Guru and above all, by the grace of Siva. When His grace sets in, the Lord reveals Himself to us and instructs us to our true nature through jnana. Jnana is the supreme means of salvation. The attainment of Sivathva or Siva- nature does not mean complete merging of soul with Siva. It continues to exist as soul in God, without loss of its individuality. This is a form of qualified Monism like Visishta- adhvaitham with some aspects of Advaitham of Sankara.

In Sakthi Yoga philosophy, Siva is omnipresent, impersonal and inactive. He is pure consciousness and Sakthi is dynamic. The creative aspect of Siva is Siva Thatthva. Sakthi-Thatthva is the will of Siva. Siva has two aspects. In one, He is the supreme consciousness and changeless Sat-Chid-Ananda, who is the Nishkala Siva and Nirguna Siva. He is not connected with Sakthi. In the other aspect, He changes as the world and the cause of this change is Siva-Thatthva. Sakthi-Thatthva is the dynamic aspect of Brahmam. Maya or Prakrithi is within the womb of Sakthi. It is the matrix of the world and is potential in the state of dissolution. She is dynamic in the act of creation and evolves into several material elements. The power or active aspect of the immanent God is Sakthi. She is the universal Mother. She is Sakthi, Durga, Lakshmi, Saraswathi, Kali, Chandi, Chamundi, Tripurasundari and Rajarajeswari. The basis of Sakthism is the Veda and is a form of Monism or Advaitha Vaada and is only Vedantha. It speaks of personal and impersonal Godhead. The aspirant thinks that the world is identical with the Divine Mother and that his own form is a form of the Divine Mother which is identical with Brahmam.

Many other systems with emphasis on Bhakthi, devotion and worship of Vishnu and Krishna, were developed by many Acharyas. Sri Vishnuswami's system is Dualistic like Madhva's Dhvaitham. Sri Nimbarka's system of philosophy is known as Dhvaitha-Adhvaitham, dualistic monism. He holds that the relation of God to soul and world is one of identity in difference. They have qualities different from God, at the same time they are no different from God who is omnipresent. Sri Vallabha's system is known as Suddha-Adhvaitham or pure monism, as he does not admit the forces of Maya. The whole world of matters and souls is real and is only a subtle form of God. Sri Chaithanya's system of Achinthya-bedha-abhedha is one of identity in difference like Nimbarka's. They see Sri Krishna in everything. They pray to God with music and songs at all times of the day. All of them teach intense and elaborate forms of Bhakthi, practice of the Devotional path, rather than philosophy.