BackgroundHuman beings and Universe have a similar design pattern (1). This design pattern is talked about across all our scriptures from Upanishads to saMkhya kArika. This design pattern is the 'four-fold' vAk.
The seven parts, nineteen faces of mandukya upanishad and the 24 parts of saMkhya kArika are talking about the same design pattern. The four-fold vAk of Brhadharanyaka Upanishad and Rg Veda are also talking about the same design pattern.
Sabda are simply oscillations. vAk is the design pattern of Universe.
Like vAk, the speech, is the expression of human beings, Universe is the expression of Atman. This is what is symbolized by the word 'Aum'.
The KaraNas/Instruments of AtmanThe physical manifestation of Atman is Energy of the Universe (2). This is the 'Mahat' or 'Buddhi' of Universe. There are five 'forms' in which this Buddhi physically manifests. They are Electric, Magnetic, Chemical/Electromagnetic, Heat and energy in physical movement.
The process manifestation of Atman is Evolution of the Universe (2). This is popularly called Brahman. This is the 'Karmic' manifestation of the Atman. There are five forms in which the 'Karma' manifests. They are the five theromdynamic processes of Isothermal, Isochoric, Isoboric, reversible and adiabatic processes.
Atman uses thirteen instruments/tools in the process of evolution. They are the 'karaNa'. Karana means 'instruments' or 'tools' by which Karma/actions are done.
The sloka 32 of saMkhya kArika says
Karaṇaṃ trayodaśavidhaṁ, tad āharaṇadhāraṇaprakāśakaram |
kāryaṃ ca tasya daśadhā, āhāryaṁ, dhāryam prakāshyaṁ ca |32|
kāryaṃ ca tasya daśadhā, āhāryaṁ, dhāryam prakāshyaṁ ca |32|
There are thirteen instruments or tools by which Atma consumes, maintains and radiates. Out of these thirteen, ten are those that are the consumed, radiated and 'held'. These ten are the subject of external or explicit actions.
The actions of consumption, radiation and maintaining are performed by these thirteen tools/instruments. Ten instruments tools perform these actions explicitly.
Antaḥkaraṇaṃ trividhaṃ, dashadhā bāhyaṃ trayasya viṣayākhyam |
sāmpratakālam bāhyaṃ, trikālam ābhyantaraṃ karaṇaṃ
The antaH KaranasAtman has three internal instruments/tools in evolving the Universe, which is not perceivable externally, which remains the same across past, present and future. These are the three antaH-karanas.
The first of the antaH-karanas, the internal instrument/tool is prakrti or the Citta (1).
Pra-krti means first of the creation, which is the background quantum oscillations of Universe. The background quantum oscillations of vacuum in Universe remain same across all the three times. They are internal in the sense, they are not perceivable externally.
The second of the antaH-karanas, the internal instrument/tool is AhamkAra, the internal energy. AhamkAra is the internal energy of a thermodynamic system that makes a matter or system what it is. Aham-kAra means one that makes the internal of a system or object.
In thermodynamic parlance it is the 'Internal energy'. Aham-kAra is internal in the sense, they are not perceived externally. Only a change in internal energy of a system can be found, not the internal energy itself.
Aham-kAra is what we call as 'Ego' in a human being. This 'sense of self', the ego, makes a human being what they are.
Prakrti or Citta and Aham-kAra the well known antaH-karanas. The vedantic philosophies often use only two antaH-karanas though saMkhya kArika specifically says there the three.
What is the third antaH-karaNa..? Before we see that, let's understand the bAhya karaNa.
The bAhya Karanas - IndriyaIn saMkhya the bAhya/external karanas/instruments of Atman are the five buddhi Indriyas (five energy forms) and five karma Indriyas (five process types).
The ten tools/instruments/karanas of Atman are called the ten Indriyas.
Indra is the binding energy that causes the proton (4). 75% of all Universe is filled with 'Protium' which is an atom made by electron surrounding proton, more popularly known as Hydrogen (H1) atom.
Proton is the first to form stable matter in the Universe. From the proton fusion with neutrons, more complex nucleus , more complex elements, complex compounds, chains of molecules and living beings evolve.
This can be visualized as energies and methods that accompany Proton or work on Proton, to evolve from a single proton to the vast, complex matter forms of the Universe.
Indriya are these energies and methods that accompany 'Indra the proton', which are deployed in evolving the proton. Indriya is translated as 'power', as they are the energies and methods.
These energies and methods (Indriyas) are the external tools of Atman. They are bAhya karaNas.
The ten IndriyasThe ten Indriyas (3) as seen earlier are
1. Energy in the magnetic field that arises due to movement of quarks and electrons called magnetic energy.
2. Energy in the electric field that arises due to positive charge of proton and negative charge of electron in an atom called electrical energy
3. Energy stored in the electromagnetic bonds between multiple atoms in compounds and in complex forms of matter called Chemical energy
4. Energy in matter due to vibration/hopping up and down of matter called Heat energy
5. Energy in the movement of matter in space called mechanical energy
6. Transfer of energy without change in temperature (Isothermal)
7. Transfer of energy without change in volume (Isochoric)
8. Transfer of energy without change in pressure (Isoboric)
9. Transfer of energy as work (change in pressure, volume or temperature, adiabatic)
10. Transfer of energy without an entropy change (reversible)
The third antaH-karaNa - Eleventh IndriyasaMkhya talks of eleven sattvika in which it talks of the ten 'Indriyas'. The Eleventh one is the 'Manas' or At-manas (1).
saMkhya describes this Manas or Atmanas as another 'Indriya', the eleventh one.
saMkhya kArika sloka 27 says
Ubhayātmakam atra manaḥ, saṃkalpakam indriyaṃ ca sādharmyāt |
guṇapariṇāmavisheshān, nānātvam bāhyabhedāsh ca
There (in sloka 26 it was talking about Indriyas and hence it refers to the Indriyas), both manas and Atmanas determine the Indriyas and their homogeneous functioning. Different combinations of gunas evolve different external forms (of matter and beings).
Atmanas by becoming the eleventh sense organ determine the homogeneous functioning of the energies and methods (Indriyas). It causes the various combinations of gunas which leads to external differentiations of matter and beings.
Thus manas or Atmanas manifests as the eleventh sense organ or Indriya, because it guides the homogeneous functioning of other ten Indriyas (energies and methods) and causing the evolution of matter and beings.
For eg., the homogeneous working of baryons and nucleus is caused by 'virutal' mediators. Baryons like protons are formed by the mediation of strong force by 'virtual' gluons. Atomic nucleus is formed by the mediation of residue of strong force by 'virtual' pions.
These are 'virtual' because there is no physical manifestation of these and at the same time, the homogeneous functioning of a baryon or nucleus cannot be explained without these 'virtual' particles. They are the manifestations of Atmanas or Manas.
In Human beings, manas is the 'virtual' that makes a biological cell to function as a cell. It is the 'virtual' that makes the cells to function as an organ and organ systems. It is the virtual that makes the organ systems to function together as a single being.
That is Atmanas or Manas, which uses the ten tools/karanas (the energies and methods or Indriyas) to further evolution, manifests itself as 'Virtual', the eleventh Indriya to make the ten energies and methods to function homogeneously and further evolution.
This eleventh Indriya, the 'Virtual', the Manas, is the third antaH-karana.