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According to this scheme, ignorance, craving and clinging belong to the group of defilements. Mental formation and becoming belong to the group of actions. The remaining seven, that is, consciousness, name and form, the six senses, contact, feeling, birth, and old age and death belong to the group of sufferings. Through this interpretation we can see how the teaching of the Four Noble Truths and particularly the teaching of the Second Noble Truth - the truth of the cause of suffering, is conjoined with the teaching of karma and rebirth; and how together these two important teachings explain in a more complete way the process of rebirth and the origination of suffering.
You may recall that in the context of the Four Noble Truths, we have said that ignorance, desire and ill-will are the causes of suffering. If we look here at the three components of dependent origination that are included in the group of defilements, we will find ignorance, craving and clinging. Here too, ignorance is the most basic. It is because of ignorance that we crave for pleasures of the senses, for existence and for non-existence. Similarly, it is because of ignorance that we cling to pleasures of the senses, to pleasant experiences, to ideas and, perhaps most significantly, to the idea of an independent, permanent self. This ignorance - craving and clinging - is the cause of actions.
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That rivulet gradually creates a channel for itself, and gradually grows into a stream. Eventually, as the channel of the stream is deepened and widened by repeated flows of water, the stream becomes a river which develops well-defined banks and a definite course. In the same way, our actions become habitual. These habits become part of our personality and we take these habits with us from life to life in the form of mental formation or habit energy.
Our actions in this life are conditioned by the habits which we have formulated over countless previous lives. So to return to the analogy of the channel of the river and the water in it, we might say that mental formations are the channel of the river, and the actions that we perform in this life are the fresh water that flow again through the eroded channel created by previous actions.
The actions that we perform in this life are represented by the component known as becoming. So here, as regards mental formation and becoming, we have the habits that we have developed over the course of countless lives combined with new actions performed in this life, and these two together result in rebirth and suffering.
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Together, these impurities of the mind and these actions result in rebirth. In other words, they result in consciousness, in name and form, in the six senses, in contact between the six senses and the objects of the six senses, in feeling which is born of that contact, in birth, and in old age and death. In this interpretation, the five components of dependent origination included in the groups of defilements and actions - ignorance, craving, clinging, mental formation and becoming - are the causes of rebirth and suffering.
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