Yogācārabhūmi-śāstra, Volume Ten (The Twelve Links of Dependent Origination)

（二十）问。若法无明为缘。彼法是行耶。设是行者。彼无明为缘耶。答。应作四句。或有行非无明为缘。谓无漏及无覆无记。身语意行。或无明为缘。而非是行。谓除行所摄有支。所余有支。或有亦无明为缘亦是行。谓福非福。不动身语意行。除如是相。是第四句。 

Explanation: Question: If a dharma arises with ignorance as its condition, is that dharma a volitional formation? If it is a volitional formation, does its arising take ignorance as its condition?

Answer: This question should be addressed in four alternatives. First, some volitional formations do not arise with ignorance as their condition, such as untainted (anāsrava) formations and bodily, verbal, and mental actions that are neither obscuring nor determinate (anivṛtāvyākṛta). Second, some dharmas do arise with ignorance as their condition, yet are not volitional formations—for example, all the links of dependent origination other than the link of formations, such as the links of consciousness, name-and-form, the six sense bases, contact, feeling, craving, grasping, becoming, birth, and aging-and-death. Third, some dharmas both arise with ignorance as their condition and are subsumed under the link of formations, such as meritorious bodily, verbal, and mental actions, non-meritorious bodily, verbal, and mental actions, and immovable bodily, verbal, and mental actions (pure formations that are neither meritorious nor non-meritorious). Fourth, apart from these dharma-marks, everything else is subsumed under the fourth alternative. 

Untainted karmic formations no longer fall within the scope of the twelve links of dependent origination; they exceed the range of the twelve links and are not formations induced by ignorance. Likewise, bodily, verbal, and mental actions that are neither obscuring nor determinate are not subsumed under ignorance and exceed the range of the twelve links; therefore they carry no karmic results of birth and death. Of the twelve links of dependent origination, eleven links are subsumed under ignorance and all contain ignorance, but ignorance giving rise to the link of formations is the most direct, while for the other links it appears relatively indirect; hence it is said that ignorance conditions volitional formations (avidyā-pratyayāḥ saṃskārāḥ). Among the link of formations subsumed under ignorance, the formations that create meritorious karma are also subsumed under ignorance: because one does not understand the principle of the Four Noble Truths and the principle of true reality, engaging in formations that seek conditioned merit is a formation of ignorance. The non-meritorious formations that create unwholesome karma are even more formations subsumed under ignorance. The formations of the immovable mind cultivated in the four dhyānas by practitioners of non-Buddhist paths are also cultivated because they do not understand the principle of liberation, and thus are likewise formations subsumed under ignorance.