The original Sankhya was monistic and theistic. But the classical Sankhya, perhaps under the influence of Materialism, Jainism and Early Buddhism, became atheistic.
It is orthodox because it believes in authority of the Veda. It does not establish the non-existence of God. It only shows that Prakrti and Purusas are sufficient to explain this universe and therefore there is no reason for postulating a hypothesis of God. But some commentators have tried to repudiate the existence of God, while the later Sankhya writers like Vijnanabhiksu have tried to revive the necessity for admitting God. Those who repudiate the existence of God give the following arguments: if God is affected by selfish motives, He is not free; if He is free, He will not create this world of pain and misery. Either God is unjust and cruel or He is not free and all-powerful. If He is determined by the law of Karma, He is not free; if not, He is a tyrant. Again, God being pure knowledge, this material world cannot spring from Him. The effects are implicitly contained in cause and the material world which is subject to change requires an unintelligent and ever-changing cause and not a spiritual and immutable God. Again, the eternal existence of the Purusas is inconsistent with God. If they are the parts of God, they must have some divine power. If they are created by God, they are subject to destruction. Hence there is no God.
Let us now proceed to give a critical estimate of the Sankhya system. The logic of the Sankhya system, like that of Jainism, impels it to embrace idealistic monism or absolutism but it clings, like Jainism, to spiritualistic pluralism and dualistic realism. The fundamental blunder of Sankhya is to treat Prakrti and Purusa as absolutely separate and independent realities. The Prakrti and Purusa of Sankhya thus become mere abstractions torn away from the context of concrete experience the object and the subject are relative and not independent and absolute. Experience always unfolds them together. Like the two sides of the same coin, they are the two aspects of the same reality. To dig a chasm between them is to undermine them both. And that is what Sankhya has done. The logic of Sankhya requires it to maintain the ultimate reality of the transcendental Purusa alone and to regard Prakrti as its inseparable power. When this Purusa is reflected in its own power Prakrti, it becomes the empirical ego, the Jiva, the phenomenal. Plurality belongs to this Jiva, not to the transcendental Purusa. The subject and the object, the Jiva and the Prakrti, are the two aspects of the Purusa which is their transcendental background. It is the Purusa which sustains the empirical dualism between Prakrti and Jiva and which finally transcends it. Every Jiva is the potential Purusa and liberation consists in the actualization of this potentiality. This is the philosophy to which the Sankhya logic points and which is throughout implicit in Sankhya, but which is explicitly rejected by Sankhya with the inevitable and unfortunate result that Sankhya has reduced itself to a bundle of contradictions.
If Prakrti and Purusa are absolute and independent, they can never come into contact and hence there can be no evolution at all. As Shankara has pointed out, Prakrti being unintelligent and Purusa being indifferent and there being no third principle, no tertium quid, there can be no connection of the two. Neither real contact (samyoga) nor semblance of contact (samyogabhasa) nor mere presence of Purusa (sannidhya-matra), as we have noticed above, can explain evolution. Sankhya realizes the mistake, but in order to defend the initial blunder it commits blunders after blunders.
The Sankhya account of Prakrti makes it a mere abstraction, an emptiness of pure object. The original state of Prakrti is not a harmony, but only a tension of the three gunas. The gunas point to a state beyond them. It is this state which gives harmony to the gunas and transcends them. Prakrti does not do that. Hence it is not real. Reality is the Purusa alone. Again, Prakrti is unconscious and unintelligent. How can it then explain the teleology which is immanent in creation? If Prakrti is unconscious and blind, evolution must be mechanical and blind and there can be no freedom of the will. And if Prakrti and all its evolutes from Mahat to the Mahabhutas tend to serve the purpose of the Purusa, it can be neither unconscious nor independent. Again, if Prakrti is blind and non-intelligent, it cannot evolve this world which is full of harmony, order, design and purpose. Stones, bricks and mortar cannot account for the design of a building. Mere clay cannot fashion itself into a pot. How can Prakrti explain the original impetus, the first push, and the elan vital which disturbs the equilibrium of the gunas? The argument that Prakrti works unconsciously for the emancipation of the Purusa just as unintelligent milk flows for the nourishment of the calf is untenable because milk flows as there is a living cow and there is the motherly love in the cow for the calf. Nor can the modification of Prakrti be compared to that of grass which turns into milk. Grass becomes milk only when it is eaten by a milch cow, and not which it lies uneaten or is eaten by a bull. The simile of the blind and the lame is also misleading since the blind and the lame are both intelligent and active beings who can devise plans to realize a common purpose, while Prakrti is unconscious and Purusa is indifferent and there is no common purpose. The simile of magnet and iron is also misleading because the proximity of the Purusa being permanent, there would be no dissolution and hence no liberation and the very state of Prakrti as the equilibrium of the gunas would be impossible since the presence of the Purusa would never permit the state of equilibrium. Moreover, activity is said to belong to Prakrti and enjoyment to Purusa. This overthrows the moral law of Karma and brings in the charge of vicarious liability. Poor Purusa suffers for no fault of its own. Prakrti performs actions and Purusa has to reap their fruits, good or bad. And Prakrti knows how to make delicious dishes, but not to enjoy them!
Though Prakrti is called absolute and independent yet there is a note of relativism in the conception of Prakrti. As a triad of the gunas it points towards the nistraigunya Purusa as the transcendental reality. At every step, it shows its dependence on Purusa. It cannot evolve this world by itself without being influenced by the Purusa— whether that influence is due to real contact or semblance of contact or mere presence. How can Prakrti be absolute then? An absolute Prakrti is a contradiction-in-terms. If it is absolute why should it care to serve the purpose of the Purusa? Does it not make it subservient to the Purusa? And if it is unconscious and blind, how can it serve this purpose? Though Sankhya calls Prakrti as impersonal, yet its descriptions of Prakrti are full of personal notes. Prakrti is called a dancing girl; she is feminine, she is virtuous and generous; she is the benefactress of the Purusa; she serves Purusa’s purpose in a spirit of perfect detachment for no gain to herself; and yet she is blind; she is extremely delicate and shy and cannot stand the eye of the Purusa; she is seven-rainbow-coloured and wants to attract the Purusa. How can such Prakrti be absolute and impersonal? Purusa is untouched by bondage, liberation and transmigration. It is Prakrti who binds herself and liberates herself and transmigrates. Prakrti is said to vanish for that Purusa who has ‘seen’ her, though she continues to exist for others. Does this not make Prakrti relative? If she ‘vanishes’, how can she be absolute and eternal? Why not frankly equate Prakrti with Avidya? Either maintain a plurality of Prakrtis or equate it with Avidya. These descriptions of Prakrti clearly show that Vedanta is implicit in Sankhya.
Sankhya throughout makes a confusion between the Purusa, the transcendental subject and the Jiva, the empirical ego, the product of the reflection of Purusa in Buddhi or Mahat. Sankhya rightly emphasizes that the Purusa is pure consciousness and that it is the foundation of all knowledge and that it is beyond bondage, liberation and transmigration. Purusa has really nothing to do with the play of Prakrti. It is a mere spectator and is not among the dramatis personae. It is not contaminated by action. It is self-proved and self-shining. It is the transcendental subject which appears as the phenomenal ego. We cannot derive consciousness from Prakrti or matter, nor can we regard consciousness as a quality. The self is not a substance but a subject. It is the Alone, the unseen seer, the transcendental Absolute. But Sankhya soon forgets its own position and reduces the ultimate Purusa to the level of the phenomenal ego. Some of the proofs advanced in support of the existence of Purusa, are proofs only for the phenomenal ego. Purusa is called enjoyer and Prakrti enjoyed. But if Purusa is the transcendental subject, how can it be an enjoyer? If it is passive, indifferent and inactive, how can it enjoy? Again, how can the transcendental reality be split into the many reals? How can there be a plurality of the transcendental subjects, the Purusas? Of course, none denies the plurality of the empirical egos, the Jivas. But the manyness of the egos, the empirical souls, does not lead us to the manyness of the transcendental selves, the Purusas. In fact, all the arguments advanced by Sankhya to prove the plurality of the Purusas turn out to be arguments to prove the plurality of the Jivas which none has ever denied. Sankhya proves the plurality of the Purusas by such flimsy arguments that if there were only one Purusa, the birth or death or bondage or liberation or experience of pleasure or pain or indifference of one should lead to the same result in the case of all, forgetting its own doctrine that the Purusa is not subject to birth or death or bondage or liberation or any action. Realizing this grave defect, the commentators like Vachaspati, Gaudapada and Vijnanabhiksu have maintained the reality of one Purusa only. If Sankhya can reduce all objects to one Prakrti, why can it not reduce all the empirical souls to one Purusa by the same logic? And why can Prakrti and the empirical Purusa be not reduced to the Absolute Purusa by the same logic? Again, if all the Purusas are essentially similar, if the essence of all is pure consciousness, how can they be really many? Differences and distinctions constitute individuality. If all the Purusas are essentially the same, there is no meaning in proclaiming their quantitative plurality. Numerical pluralism is sheer nonsense.
Another grave defect in Sankhya is in its conception of liberation. Liberation is regarded as a negative cessation of the three kinds of pain and not as a state of positive bliss. Sankhya feels that bliss is a product of Sattva guna and cannot remain in liberation which is the state beyond the gunas. But Sankhya forgets that the bliss in liberation is not empirical happiness produced by sattva. This bliss is also transcendental in character. It is beyond both pain and pleasure. What is related to pain is empirical pleasure and not transcendental bliss. The negative Kaivalya suggests an influence of the Hinayana Nirvana. Will the liberated Purusas, the eternally isolated units not represent a vast array of sad personalities? If liberation is an annihilation (nasmi, naham) of human personality and not its perfection, the ideal of liberation is most uninspiring. It must be substituted by an ideal of positively blissful eternal existence in the bosom of the Absolute.
Sankhya, therefore, should let its Prakrti glide into Avidya, the inseparable power of the Purusa; its Prakrti-parinama-vada into Purusavivarta- vada ; its so-called empirical Purusa into phenomenal Jiva; its negative Kaivalya into positively blissful Moksa, and should, instead of maintaining the plurality of Purusas and creating an unbridgeable chasm between the subject and the object, recognize the Absolute Purusa, the transcendental subject which gives life and meaning to the empirical subject and object and holds them together and ultimately transcends them both.