The speculations of which we see the commencement and progress in the Upanishads were finally developed Six philosophic schools.and classified in a series of writings called the six Sastras or darsanas. These constitute the regular official philosophy of India. They are without much difficulty reducible to three leading schools of thought—the Nyaya, the Sankhya, and the Vedanta.
Roundly, and speaking generally, we may characterize these systems as theistic, atheistic, and pantheistic respectively.
It is doubtful, however, whether the earlier form The Nyaya.of the Nyaya was theistic or not. The later form is so, but it says nothing of the moral attributes of God, nor of his government. The chief end of man, according to the Nyaya, is deliverance from pain; and this is to be attained by cessation from all action, whether good or bad.
The Sankhya declares matter to be self-existent The Sankhya.and eternal. Soul is distinct from matter, and also eternal. When it attains true knowledge it is liberated from matter and from pain. The Sankhya holds the existence of God to be without proof.
But the leading philosophy of India is unquestionably the Vedanta. The name means "the end or scope of the Veda;" and if the Upanishads were the Veda, instead of treatises tacked on to The Vedanta.it, the name would be correct; for the Vedanta, like the Upanishads, inculcates pantheism.
The form which this philosophy ultimately assumed is well represented in the treatise called the Vedanta Sara, or essence of the Vedanta. A few extracts will suffice to exhibit its character. "The unity of the soul and God—this is the scope of all Vedanta treatises." We have frequent references made to the "great saying," Tat twam—that is, That art thou, or Thou art God; and Aham Brahma, that is, I am God. Again it is said, "The whole universe is God." God is "existence (or more exactly an existent thing[15]), knowledge, and joy." Knowledge, not a knower; joy, not one who rejoices.
Every thing else has only a seeming existence, which is in consequence of ignorance (or It teaches absolute idealism.illusion). Ignorance makes the soul think itself different from God; and it also "projects" the appearance of an external world.
"He who knows God becomes God." "When He, the first and last, is discerned, one's own acts are annihilated."
Meditation, without distinction of subject and object, is the highest form of thought. It is a high attainment to say, "I am God;" but the consummation is when thought exists without an object.
There are four states of the soul—waking, dreaming, dreamless sleep, and the "fourth state," or pure intelligence. The working-man is in dense ignorance; in sleep he is freed from part of this ignorance; in dreamless sleep he is freed from still more; but the consummation is when he attains something beyond this, which it seems cannot be explained, and is therefore called the fourth state.