The second Truth declares the origin of suffering. "It is," says the Buddha, "the thirst which causes rebirth, which is accompanied by pleasure and lust and takes delight now here, now there; namely, the thirst for pleasure, the thirst for another life, the thirst for success." This Thirst (Taṇhâ) is the craving for life in the widest sense: the craving for pleasure which propagates life, the craving for existence in the dying man which brings about another birth, the craving for wealth, for power, for pre-eminence within the limits of the present life. What is the nature of this craving and of its action? Before attempting to answer we must consider what is known as the chain of causation[442], one of the oldest, most celebrated, and most obscure formulæ of Buddhism. It is stated that the Buddha knew it before attaining enlightenment[443], but it is second in importance only to the four truths, and in the opening sections of the Mahâvagga, he is represented as meditating on it under the Bo-tree, both in its positive and negative form. It runs as follows: "From ignorance come the sankhâras, from the sankhâras comes consciousness, from consciousness come name-and-form, from name-and-form come the six provinces (of the senses), from the six provinces comes contact, from contact comes sensation, from sensation comes craving, from craving comes clinging, from clinging comes existence, from existence comes birth, from birth come old age and death, pain and lamentation, suffering, sorrow, and despair. This is the origin of this whole mass of suffering. But by the destruction of ignorance, effected by the complete absence of lust, the sankhâras are destroyed, by the destruction of the sankhâras, consciousness is destroyed" and so on through the whole chain backwards. The chain is also known as the twelve Nidânas or causes. It is clearly in its positive and negative forms an amplification of the second and third truths respectively, or perhaps they are a luminous compendium of it. Besides the full form quoted above there are shorter versions. Sometimes there are only nine links[444] or there are five links combined in an endless chain[445]. So we must not attach too much importance to the number or order of links. The chain is not a genealogy but a statement respecting the interdependence of certain stages and aspects of human nature. And though the importance of cause (hetu) is often emphasized, the causal relation is understood in a wider sense than is usual in our idiom. If there were no birth, there would be no death, but though birth and death are interdependent we should hardly say that birth is the cause of death.