The development of religious and philosophic thought in India comprises a many-sided presentation of the higher aspirations in man. While the Veda-Samhitas embody the prayers of the human spirit to the Universal Reality revealed in creation and record the vision of the One in the many, the Upanishads represent an attempt to dive into the One from the forms of the many. Though modern history sees an advance of thought from the Samhitas to the Upanishads, tradition does not permit any such bifurcation and sees in them two types of the vision of Reality, the former emphasising its aspect as creation and the latter its being, as it is. There is, no doubt, a tendency to view the essential nature of Reality as transcending creation, but it is not possible to ignore the creational aspect as a realm outside Reality, for creation also is within it. From this point of view, it seems quite reasonable to follow the way of ancient tradition that the Samhitas and the Upanishads are not to be divided as inferior and superior, but as pictures of one side and another side of Reality. It is an important aspect in the interpretation of the Vedas to regard them as a single body of scriptural lore, of which the Upanishads form the consummation. Without taking the purely historical view that the Upanishads transcend the Samhitas in their value, the former may be said to be an improvement upon the content of the latter in the sense that the Samhitas look upon creation and its Maker more in their cosmological significance maintaining a kind of awe-inspiring distance between man and God, while the Upanishads stir up within man a consciousness of the immediacy, in his own being, of that cosmic grandeur of God in creation. The distinction of God, world and soul, when it is handled by the Upanishads, resolves itself into the unitary Absolute.
But a very meaningful point of view which is sought to be emphasised here is the importance of the Epics and Puranas in the history of Indian thought. The ancient sages were quick to appreciate the necessity to appeal to the various sides of human nature and to alter the method of teaching in adjustment with this need. As it was stated earlier, Reality and creation are not to be regarded as two facts or problems to be encountered but two ways of witnessing the same thing. The human mind is composed not only of the rational powers but also the emotional and the instinctive elements which feel the presence and working of certain truths that rationality cannot explain adequately. The Epics and Puranas answer to that aspect of human nature which is other than the ratiocinating or the investigative. It is human egoism which asserts that only scientific discoveries and affirmations in their modern sense are real and there is nothing true in the world which observation and experiment cannot certify. It is forgotten that reason is not all and science is not the last word in knowledge. The heart revolts against the conclusion of science that tears of grief consist merely of certain chemical substances or that the beauty of a painting is just the effect of a combination of colours. Religion, likewise, is not an invention of human crotchet or an outcome of fear or even a social necessity but the answer to a living surge of conscious aspiration which cannot be intelligible either to reason or to science. Human nature is not a combination of scientific facts or a bundle of physical laws or chemical elements, but manifests in itself a meaning higher than all observable values in the world of mathematics, physics, chemistry or biology. The religious spirit of the Epics and Puranas is different from the beaten track of logical philosophy, for it reads an eternal meaning in the temporal structure of the world. The power and purpose of an Avatara, for example, infuses into the historical process of the universe a truth which is above history. Everything that is human has a touch of the mathematical and the logical in it - - whether it is history, or science. But the eternal religion is that which feels the existence and activity of a supernal Reality, even in what is earthly. The personalities and events described in the Puranas cannot always be taken as myths and fables which have no substance in them, for the universe is nothing but the Absolute beheld through the channels of human perception. In their attempt at a bringing together of the temporal and the eternal, the Epics present before us a picture of divine perfection commingled with human weakness. In these records of cosmic history, the usual meanings of past, present and future assume a different suggestiveness and it is futile to read into them a mere human viewpoint of understanding. It is here that we come face to face with the fact that religion is neither a social practice nor a human contrivance but the perennial activity of timeless being.
The Bhagavadgita is a part of the Mahabharata and thus occurs in the context of an Epic, and so it is called a smriti (secondary revelation), as distinguished from the sruti (primary revelation), which are the Vedas and the Upanishads. Yet, the Gita plays a unique role in the history of religious and philosophic thought. The Upanishads are like an extensive forest ranging over a wide area and covering almost everything which may be said to be of the nature of reality.
The Bhagavadgita is, on the other hand, a kind of garden of select plantations which are deliberately nurtured, keeping in view the needs of human psychology. It is at once rationalistic, volitional, emotional and charged with a high spirit of activity. In the Upanishads, Reality seems to be musing over itself and contemplating its own glories, while in the Bhagavadgita it speaks to man in a language which is intelligible to the mind that sees meaning in pleasure and pain, reward and punishment, progress and evolution, bondage and liberation. The Bhagavadgita is a world-gospel which tries to link man with God, enlighten him on the concrete relation subsisting between the world and the Absolute, and solace him that there is a way leading from the finite to the Infinite.
Nevertheless, the Upanishads may be said to have sown the seeds for every thought that occurred later In spite of their excessive concern with the trans-empirical Reality, whatever be its relation to the cosmos of creation, they make here and there profound statements, though at random, which sum up the principles of ethics, psychology and the path that leads to the Supreme Being. The Bhagavadgita is a detailed accentuation of some of the terse observations made already in the Upanishads. We have, for example, a statement on the nature of the universal Virat in a single verse of the Mundaka Upanishad, which may itself be said to be an inspiration after the Purushasukta of the Samhitas. The Isa, Katha and the Svetasvatara Upanishads have verses that embody some of the important themes of the Bhagavadgita, which, on the whole, manifests the spirit of God descended into the field of action.
The Yoga-Vasishtha rises to a high watermark in the philosophic thought of India. It is a classic inimitable in its kind. Through elaborate descriptions, almost in an epic style, it works upon the fundamental principles enunciated in the Upanishads and combines philosophy with a lofty psychology by which it explains creation, evolution and involution purely from a spiritualistic point of view. In this way, it tries to give an ultimate explanation of everything in terms of the Infinite consciousness which manifests itself as the objects of experience on one side and the experiencing subjects on the other side. The sorrows which follow in the wake of every effort of man for acquisition of happiness in a world of transient phenomena, the knowledge needed to diagnose the common malady of everyone, and the ethical prerequisites to be cultivated for the attainment of true freedom are its main subjects. The uniqueness of the methodology of the Yoga-Vasishtha is in its attempt to analyse all things in terms of consciousness which is the ultimate reality of everything. Health and disease, happiness and misery, success and failure, bondage and freedom are all explicable in terms of the right adjustment or maladjustment of consciousness. Finally, even birth and death are traced to this mysterious cause which cannot be directly seen, as it is involved in the seeing consciousness itself. Another text, known as the Tripurarahasya (Jnana-kanda), follows the lead of the Yoga-Vasishtha in the treatment of a spiritual idealism which it regards as the alpha and omega of all things.
An interesting part of the manifestation of Indian Philosophy as religion is its concept of the pantheon which has an immense practical significance in the day-to-day life of the country. The gods (devatas) hold such sway over the minds of persons that the theological evaluation of life may be regarded as a commonplace throughout India. A final interpretation of any problem hinges upon a Daiva or a presiding deity, a heritage of thought which may be said to have directly come down to the present day from the Upanishads that viewed the universe as constituted of the object (adhibhuta), subject (adhyatma) and deity (adhidaiva). There is nothing which is not involved in this triadic relation, in any stage of creation. It is interesting to note this concept of deity entering as an invariable concomitant of every stratum of evolution in the recent philosophy of emergent evolution, particularly in Samuel Alexander; who propounds this theme in his Space, Time and Deity. Herein he makes the principle of deity unavoidable in the evolutionary process on a nisus to progress upwards. It is needless to add that the Upanishads have already, many centuries back, anticipated in their intuitions this novel doctrine of deity; with an added significance and purpose, and even today it is impossible to remove from the minds of the Indian people the belief in the governance of the subject-object relation by a presiding deity. It is this presiding principle which the Bhagavadgita confirms as the final deciding factor in all actions and processes of man and the world. The crystallisation of this doctrine is the great religious theology of India, which posits various deities as the guardians of the cosmos and sets forth rules of their worship in the interest of man's march towards his great destiny. Theology is an essential part of religion, which is a name for philosophy in practice.
The rules of conduct are a part of the religious way of life. The Smritis are the codes which lay down the laws of human behaviour in one's personal capacity as well as in society. The ancient dictum of the Veda that satya (truth as being) and rita (truth as law) are the primary principles of Reality and its manifestation is the background of the canons of dharma, or a life of righteousness. It is the intention of the Smritis to make explicit the forms of righteousness as they manifest themselves in practical life, which are only implicit in the principles of satya and rita or in the account of creation given in the Upanishads. The modes of living according to class (varna) and order (ashrama) instituted for the purpose of ensuring mutual cooperation in society are the main contents of the Smritis. These texts not only deal with the ethical problems of man as an individual and as a member of a family or of society in general, but also dilate upon the rules of administration, politics and statesmanship, legal principles and statecraft. The Smritis of Manu, Yajnavalkya and Parasara, the Santi-Parva of the Mahabharata and the Arthasastra of Kautilya are the primary sources of information on this subject. The social, political and legal systems enunciated in these codes are ultimately spiritual in their tone, for they analyse the life of man into the fourfold scheme of practical endeavour, known as rectitude of conduct (dharma), and a righteous pursuit of economic values (artha) and of the fulfilment of one's normal desires (kama), to culminate in the blossoming of the flower of existence into the experience of eternal bliss (moksha). There is, thus, no clash between the individual and society, man and the State, or between God and creation.