Samudaya

The Twelve Nidānas (Pali/Sanskrit: nidāna "cause, motivation, link") is a doctrine of Buddhism where each link is asserted as a primary causal relationship between the connected links. These links present the mechanistic basis of repeated birth, Samsara, and resultant Dukkha (suffering, pain, unsatisfactoriness) starting from avidyā (ignorance, misconceptions).

The Twelve Nidānas doctrine is one application of the Buddhist concept of pratītyasamutpāda or Paticcasamuppada ("Dependent Arising" or "Dependent Origination").

Several series of Nidānas are described in the suttas.

Dīgha Nikāya Sutta 1, the Brahmajala Sutta, verse 3.71 describes six Nidānas:

[...] [T]hey experience these feelings by repeated contact through the six sense-bases; feeling conditions craving; craving conditions clinging; clinging conditions becoming; becoming conditions birth; birth conditions aging and death, sorrow, lamentation, sadness and distress.

Dīgha Nikāya, Sutta 14 describes ten links, and in Sutta 15 nine links are described, but without the six sense‑bases.

The Twelve Nidānas are explained in detail in the Visuddhimagga of Buddhaghosa, the central text of the Mahāvihāra commentarial tradition. Buddhaghosa recounts four methods to interpret the Twelve Nidanas:

The first method begins with ignorance and proceeds to sickness, old age, and death. The second method begins with attachment and proceeds to birth. The third method begins with birth and proceeds back to ignorance. The fourth method begins with attachment and proceeds to ignorance.

The following description would provide some further insight into this concept/phenomenon...

Thus one could observe that:

1. Due to ignorance (of underlying realities of existence) we process/ferment what comes to our mind.

2. This processing/fermentation causes karma to form and mould the status consciousness (vinyana).

3. The functioning/existence of the status consciousness has a close association with regards to sustaining life (one's existence).

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