Yogācārabhūmi-śāstra, Volume 34 (40)

Original text:由如是等。比度增上作意力故。于有他世诸行生起。获得决定。如是略由三种增上作意力故。寻思观察。内外诸行是无常性。谓净信增上作意力故。现见增上作意力故。比度增上作意力故。于前所举。能随顺修无常五行已。辩变异灭坏二行。

Explanation: Because of the aforementioned power of intensified mental engagement (adhimātramanaskārabala) through inference, one gains certainty and conviction regarding the arising of the formations of past and future lives. Broadly speaking, through three kinds of power of intensified mental engagement, one can seek out and contemplate that the formations, both internal and external, are impermanent in nature. The three kinds of power of intensified mental engagement are: the power of intensified mental engagement through pure faith, the power of intensified mental engagement through direct seeing, and the power of intensified mental engagement through inference. With regard to the internal and external formations enumerated earlier, one is able to cultivate in accord with the five contemplations of impermanence, and then discern the two contemplations of mutation and destruction.

When it is necessary to contemplate the impermanence of the five aggregates of past and future lives, one must, on the basis of contemplating the five aggregates of the present life according to reality through valid direct cognition, correctly contemplate by inference the five aggregates of past and future lives in order to attain realization and knowledge. The two dharmas being compared by inference must be of the same category; dharmas of different categories cannot be compared by inference. On the basis of contemplating the present five aggregates according to reality through valid direct cognition, one can correctly contemplate by inference the five aggregates that have already passed, as well as those that will appear in the future. In this way one can attain realization and knowledge, and the mind can gain certainty and confirmation regarding the impermanence of all formations.