The Sanathana Dharma philosophy has three broad schools of thought, Dvaita, Vishista Dvaita and Advaita. All three schools believe in the individual soul (Atma) and the universal soul (Paramatma)
Dvaita (duality) school believes that the Atma is separate and the Paramatma is separate. The Atma is governed by the Paramatma, but remains separate through all its births and existence.
Vishista Dvaita (Qualified duality) believes that the Atma separates from the Paramatma, and remains separate in all its worldly births, but ultimately joins and becomes one with the Paramatma.
Advaita ( Non-dualism) believes that the Atma and Paramatma are one and the same, and the division is only in perception, due to Maya (illusion).
Hindu culture should be differentiated from Hindu religious culture – i.e – Hindu religion (Sanathana Dharma) Hindu culture need not include religion. Culture is a broader concept of which religion is only one aspect.
Atheism is an (accepted) part of Hinduism the culture, but obviously cannot be true of Hinduism the religion.
(In a lighter vein, its like someone said,’Thank God, I am an atheist!’)
Theism, agnosticism, atheism etc are states of the mind with relation to belief in a God or a divine entity. This is present in any human in any culture.
Once you are within the Hindu religious fold, then the streams of Hindu philosophical belief (strictly philosophy) are Dvaita, Visishta Dvaita and Advaita. These should not be confused with the ritual and social aspects of Hindu religion and theology.
Hinduism
Six Astika schools
- Sankhya (non-theistic duality)
- Yoga (self discipline or self realization)
- Nyaya (The philosophy of logic and reasoning)
- Vaisesika (The Vedic atomic theory)
- Karma Mimansa (elevation through the performance of duty)
- Vedanta (the conclusion of Vedic revelation).
Sixth school has branches:
- Advaita
- Dvaita
- Achintya Bheda Abheda
- Vishishtdvaita
- Shuddha dvaita and
- Dvaita Advaita
Of these six, the first four are the ones which are mostly followed.
Other schools:
- Pasupata
- Saiva
- Pratyabhijña
- Raseśvara
- Īśvara
- Pāṇini Darśana
- Charvaka
Nyaya Philosophy
Sankhya Philosophy
Yoga Philosophy
Vaisheshika
Purva Mimamsa
Purva Mimamsa school believes in the complete authority of Vedas. It is based on sage Jaimini’s Mimamsa Sutras. It emphasizes the power of yajnas and mantras in sustaining the activities of the universe. It states that a human being can attain salvation only by acting in conformity with the principles of Vedas.
Uttara Mimamsa (Vedanta)
Vedanta school is a monistic school of philosophy that believes that the world is unreal and the only reality is Brahman. The three sub-branches of Vedanta are Advaita of Shankaracharya, Vishishta Advaita of Ramanujacharya and Dvaita of Madhwacharya. Uttara Mimamsa is based on Upanishads (the end portions of Vedas).
I recommend please read the following books to understand hinduism better.
- Understanding sanatan dharma by NK TAWAKLEY
- The essentials of Indian philosophy by M Hiriyanna
- The Hindu mind by Bansi Pandit
Satyamshakti Spirituality Journal
Why India doesn’t have psychologists anymore
Creating A Yogic Path With Badhak and Sadhak Tattvas
