I. _The Karma Theory._
It is, however, remarkable that with the exception of the Carvaka materialists all the other systems agree on some fundamental points of importance. The systems of philosophy in India were not stirred up merely by the speculative demands of the human mind which has a natural inclination for indulging in abstract thought, but by a deep craving after the realization of the religious purpose of life. It is surprising to note that the postulates, aims and conditions for such a realization were found to be identical in all the conflicting systems. Whatever may be their differences of opinion in other matters, so far as the general postulates for the realization of the transcendent state, the _summum bonum_ of life, were concerned, all the systems were practically in thorough agreement. It may be worth while to note some of them at this stage.
First, the theory of Karma and rebirth. All the Indian systems agree in believing that whatever action is done by an individual leaves behind it some sort of potency which has the power to ordain for him joy or sorrow in the future according as it is good or bad. When the fruits of the actions are such that they cannot be enjoyed in the present life or in a human life, the individual has to take another birth as a man or any other being in order to suffer them.
The Vedic belief that the mantras uttered in the correct accent at the sacrifices with the proper observance of all ritualistic details, exactly according to the directions without the slightest error even in the smallest trifle, had something like a magical virtue automatically to produce the desired object immediately or after a lapse of time, was probably the earliest form of the Karma doctrine. It postulates a semi-conscious belief that certain mystical actions can produce at a distant time certain effects without the ordinary process of the instrumentality of visible agents of ordinary cause and effect. When the sacrifice is performed, the action leaves such an unseen magical virtue, called the _ad@r@s@ta_ (the unseen) or the _apurva_ (new), that by it the desired object will be achieved in a mysterious manner, for the _modus operandi_ of the _apurva_ is unknown. There is also the notion prevalent in the Sa@mhitas, as we have already noticed, that he who commits wicked deeds suffers in another world, whereas he who performs good deeds enjoys the highest material pleasures. These were probably associated with the conception of _@rta_, the inviolable order of things. Thus these are probably the elements which built up the Karma theory which we find pretty well established but not emphasized in the Upani@sads, where it is said that according to good or bad actions men will have good or bad births.
To notice other relevant points in connection with the Karma doctrine as established in the astika systems we find that it was believed that the unseen (_ad@r@s@ta_) potency of the action generally required some time before it could be fit for giving the doer the merited punishment or enjoyment. These would often accumulate and prepare the items of suffering and enjoyment for the doer in his next life. Only the fruits of those actions which are extremely wicked or particularly good could be reaped in this life. The nature of the next birth of a man is determined by the nature of pleasurable or painful experiences that have been made ready for him by his maturing actions of this life. If the experiences determined for him by his action are such that they are possible to be realized in the life of a goat, the man will die and be born as a goat. As there is no ultimate beginning in time of this world process, so there is no time at which any person first began his actions or experiences. Man has had an infinite number of past lives of the most varied nature, and the instincts of each kind of life exist dormant in the life of every individual, and thus whenever he has any particular birth as this or that animal or man, the special instincts of that life (technically called _vasana_) come forth. In accordance with these vasanas the person passes through the painful or pleasurable experiences as determined for him by his action. The length of life is also determined by the number and duration of experiences as preordained by the fructifying actions of his past life. When once certain actions become fit for giving certain experiences, these cannot be avoided, but those actions which have not matured are uprooted once for all if the person attains true knowledge as advocated by philosophy. But even such an emancipated (_mukta_) person has to pass through the pleasurable or painful experiences ordained for him by the actions just ripened for giving their fruits. There are four kinds of actions, white or virtuous (_s'ukla_), black or wicked (_k@r@s@na_), white-black or partly virtuous and partly vicious (_s'ukla-k@r@s@na_) as most of our actions are, neither black nor white (_as'uklak@r@s@na_), i.e. those acts of self-renunciation or meditation which are not associated with any desires for the fruit. It is only when a person can so restrain himself as to perform only the last kind of action that he ceases to accumulate any new karma for giving fresh fruits. He has thus only to enjoy the fruits of his previous karmas which have ripened for giving fruits. If in the meantime he attains true knowledge, all his past accumulated actions become destroyed, and as his acts are only of the as'uklak@r@s@na type no fresh karma for ripening is accumulated, and thus he becomes divested of all karma after enjoying the fruits of the ripened karmas alone.
The Jains think that through the actions of body, speech and mind a kind of subtle matter technically called karma is produced. The passions of a man act like a viscous substance that attracts this karma matter, which thus pours into the soul and sticks to it. The karma matter thus accumulated round the soul during the infinite number of past lives is technically called _karmas'arira_, which encircles the soul as it passes on from birth to birth. This karma matter sticking to the soul gradually ripens and exhausts itself in ordaining the sufferance of pains or the enjoyment of pleasures for the individual. While some karma matter is being expended in this way, other karma matters are accumulating by his activities, and thus keep him in a continuous process of suffering and enjoyment. The karma matter thus accumulated in the soul produces a kind of coloration called _les'ya_, such as white, black, etc., which marks the character of the soul. The idea of the s'ukla and k@r@s@na karmas of the Yoga system was probably suggested by the Jaina view. But when a man is free from passions, and acts in strict compliance with the rules of conduct, his actions produce karma which lasts but for a moment and is then annihilated. Every karma that the sage has previously earned has its predestined limits within which it must take effect and be purged away. But when by contemplation and the strict adherence to the five great vows, no new karma is generated, and when all the karmas are exhausted the worldly existence of the person rapidly draws towards its end. Thus in the last stage of contemplation, all karma being annihilated, and all activities having ceased, the soul leaves the body and goes up to the top of the universe, where the liberated souls stay for ever.
Buddhism also contributes some new traits to the karma theory which however being intimately connected with their metaphysics will be treated later on.
2. _The Doctrine of Mukti_.
Not only do the Indian systems agree as to the cause of the inequalities in the share of sufferings and enjoyments in the case of different persons, and the manner in which the cycle of births and rebirths has been kept going from beginningless time, on the basis of the mysterious connection of one's actions with the happenings of the world, but they also agree in believing that this beginningless chain of karma and its fruits, of births and rebirths, this running on from beginningless time has somewhere its end. This end was not to be attained at some distant time or in some distant kingdom, but was to be sought within us. Karma leads us to this endless cycle, and if we could divest ourselves of all such emotions, ideas or desires as lead us to action we should find within us the actionless self which neither suffers nor enjoys, neither works nor undergoes rebirth. When the Indians, wearied by the endless bustle and turmoil of worldly events, sought for and believed that somewhere a peaceful goal could be found, they generally hit upon the self of man. The belief that the soul could be realized in some stage as being permanently divested of all action, feelings or ideas, led logically to the conclusion that the connection of the soul with these worldly elements was extraneous, artificial or even illusory. In its true nature the soul is untouched by the impurities of our ordinary life, and it is through ignorance and passion as inherited from the cycle of karma from beginningless time that we connect it with these. The realization of this transcendent state is the goal and final achievement of this endless cycle of births and rebirths through karma. The Buddhists did not admit the existence of soul, but recognized that the final realization of the process of karma is to be found in the ultimate dissolution called Nirva@na, the nature of which we shall discuss later on.
3. _The Doctrine of Soul_.
All the Indian systems except Buddhism admit the existence of a permanent entity variously called atman, puru@sa or jiva. As to the exact nature of this soul there are indeed divergences of view. Thus while the Nyaya calls it absolutely qualityless and characterless, indeterminate unconscious entity, Sa@mkhya describes it as being of the nature of pure consciousness, the Vedanta says that it is that fundamental point of unity implied in pure consciousness (_cit_), pure bliss (_ananda_), and pure being (_sat_). But all agree in holding that it is pure and unsullied in its nature and that all impurities of action or passion do not form a real part of it. The _summum bonum_ of life is attained when all impurities are removed and the pure nature of the self is thoroughly and permanently apprehended and all other extraneous connections with it are absolutely dissociated.