The object of the system set forth in these works is strictly practical.  In the first words of the Sankhya-pravacana, the complete cessation of suffering is the end of man, and the Sankhya is devised to enable him to attain it.  Another formula divides the contents of the Sankhya into four topics—­(a) that from which man must liberate himself, or suffering, (b) liberation, or the cessation of suffering, (c) the cause of suffering, or the failure to discriminate between the soul and matter, (d) the means of liberation, or discriminating knowledge.  This division obviously resembles the four Truths of Buddhism.  The object proposed is the same and the method analogous, though not identical, for Buddhism speaks as a religion and lays greater stress on conduct.

The theory of the Sankhya, briefly stated, is this.  There exist, uncreated and from all eternity, on the one side matter and on the other individual souls.  The world, as we know it, is due entirely to the evolution of matter.  Suffering is the result of souls being in bondage to matter, but this bondage does not affect the nature of the soul and in one sense is not real, for when souls acquire discriminating knowledge and see that they are not matter, then the bondage ceases and they attain to eternal peace.

The system is thus founded on dualism, the eternal antithesis between matter and soul.  Many of its details are comprised in the simple enumeration of the twenty-five Tattvas or principles[743] as given in the Tattva-samasa and other works.  Of these, one is Purusha, the soul or self, which is neither produced nor productive, and the other twenty-four are all modifications of Prakriti or matter, which is unproduced but productive.  Prakriti means the original ground form of external existence (as distinguished from Vikriti, modified form).  It is uncreated and indestructible, but it has a tendency to variation or evolution.  The Sankhya holds in the strictest sense that ex nihilo nihil fit.  Substance can only be produced from substance and properly speaking there is no such thing as origination but only manifestation.  Causality is regarded solely from the point of view of material causes, that is to say the cause of a pot is clay and not the action of the potter.  Thus the effect or product is nothing else than the cause in another shape:  production is only manifestation and destruction is the resolution of a product into its cause.  Instead of holding like the Buddhists that there is no such thing as existence but only becoming, the Sankhya rather affirms that there is nothing but successive manifestations of real existence.  If clay is made into a pot and the pot is then broken and ground into clay again, the essential fact is not that a pot has come into existence and disappeared but that the clay continuously existing has undergone certain changes.