Tattva is a Sanskrit word meaning 'thatness', 'principle', 'reality' or 'truth'. According to various Indian schools of philosophy, a tattva is an element or aspect of reality conceived as an aspect of deity. Although the number of tattvas varies depending on the philosophical school, together they are thought to form the basis of all our experience. The Samkhya philosophy uses a system of 25 tattvas, while Shaivism recognises 36 tattvas.
Tattvas in Samkhya 
The Samkhya philosophy regards the Universe as consisting of two eternal realities: Purusha and Prakrti. It is therefore a strongly dualist philosophy. The Purusha is the centre of consciousness, whereas the Prakriti is the source of all material existence. The twenty-five tattva system of Samkhya concerns itself only with the tangible aspect of creation, theorizing that Prakriti is the source of the world of becoming. It is the first tattva and is seen as pure potentiality that evolves itself successively into twenty-four additional tattvas or principles.
Tattvas in Shaivism 
- Shuddha tattvas
- The first five tattvas are known as the shuddha or 'pure' tattvas. They are also known as the tattvas of universal experience.
- Shuddha-ashuddha tattvas
- The next seven tattvas (6–12) are known as the shuddha-ashuddha or 'pure-impure' tattvas. They are the tattvas of limited individual experience.
- Ashuddha tattvas
- The last twenty-four tattvas (13–36) are known as the ashuddha or 'impure' tattvas. The first of these is prakriti and they include the tattvas of mental operation, sensible experience, and materiality.
Within Puranic literatures and general Vaishnava philosophy tattva is often used to denote certain categories or types of being or energies such as :
- The Supreme personality of Godhead. The causative factor of everything including other Tattva(s).
- Any incarnation or expansion of Krishna.
- The multifarious energies of the Lord Krishna. It includes his internal potency Yoga Maya and material prakrti
- The living souls (jivas).
- Lord Siva (excluding the Rudra(s)) is not considered to be a jiva.
- The total material energy (prakrti).
"Spiritually there are no differences between these five tattvas, for on the transcendental platform everything is absolute. Yet there are also varieties in the spiritual world, and in order to taste these spiritual varieties one should distinguish between them".
Tattva in Jainism 
Jain philosophy can be described in various ways, but the most acceptable tradition is to describe it in terms of the Tattvas or fundamentals. Without knowing them one cannot progress towards liberation. They are:
- Jiva - Souls and living things
- Ajiva - Non-living things
- Punya - Results of Good Deeds (Good Karma)
- Pap - Results of Bad Deeds (Bad Karma)
- Asrava - Influx of karma
- Bandha - The bondage of karma
- Samvara - The stoppage of influx of karma
- Nirjara - Shedding of karma
- Moksha - Liberation or Salvation
Each one of these fundamental principles are discussed and explained by Jain Scholars in depth. There are two examples that can be used to explain the above principle intuitively.
(1) A man rides a wooden boat to reach the other side of the river. Now the man is Jiva, the boat is ajiva. Now the boat has a leak and water flows in. That incoming of water is Asrava and accumulating there is Bandh, Now the man tries to save the boat by blocking the hole. That blockage is Samvara and throwing the water outside is Nirjara. Now the man crosses the river and reaches his destination, Moksha.
(2) Consider a family living in a house. One day, they were enjoying a fresh cool breeze coming through their open doors and windows of the house. However, the weather suddenly changed to a terrible dust storm. The family, realizing the storm, closed the doors and windows. But, by the time they could close all the doors and windows some of the dust had been blown into the house. After closing the doors and the windows, they started clearing the dust that had come in to make the house clean again.
This simple scenario can be interpreted as follows:
1) Jivas are represented by the living people.
2) Ajiva is represented by the house.
3) Punya is represented by enjoyment resulting from the nice cool breeze.
4) Pap is represented by discomfort resulting from the storm.
5) Asrava is represented by the influx of dust.
6) Bandh is represented by the accumulation of dust in the house.
7) Samvar is represented by the closing of the doors and windows to stop the accumulation of dust.
8) Nirjara is represented by the cleaning up of already collected dust from the house.
9) Moksha is represented by the cleaned house, which is similar to the shedding off all karmic particles from the soul.
See also 
- Prasad, Ram (1997). Nature's Finer Forces: The Science of Breath and the Philosophy of the Tattvas. Kessinger. ISBN 1-56459-803-9
- Ramacharaka Yogi (1997). Science of Breath. Kessinger. ISBN 1-56459-744-X
- Singh, Jaideva (1979). Siva Sutras: The Yoga of Supreme Identity. Delhi: Motilal Banarsidas.
- Tattvakosha - An Encyclopedia on Absolute Truth in a Vedic paradigm.
Further reading 
- Swami Satyananda Saraswati. Tattva Jnana. Devi Mandir. ISBN 1-877795-62-3.
- Uses of 'tattva' in Puranic and Gaudiya Vaishnava literature.
- Articles on Absolute Truth in a Vedic paradigm.