成唯識論演祕 3.103

3.103

Answer: Asabhāva's commentary on the Mahāyānasaṃgraha, fascicle two, explains this in full. In brief, it states: If the two bījas were only generative causes (janma-hetu) and not inducing causes (ākarṣaṇa-hetu), grain bījas gathered and stored in granaries and the like should not continue in a similar succession for a long time; and the sequential continuation of states such as blue-black swelling and putrefaction of a corpse after death should also not occur. Why? The moment death occurs, it should instantly perish and disintegrate. How could it be likened to perishing naturally later on? Just as when shooting an arrow and releasing the bowstring, the force of the movement serves as the generative cause that makes the arrow leave the string without immediately falling; and the force of drawing the bow serves as the inducing cause of the arrow, causing the arrow to travel forward and reach a distance. It is not that the force of releasing the string alone is generative, for then it should immediately drop; nor is it that the impetus successively pushes it forward, for then it should never drop. Since it leaves the string and travels far to reach a destination, we know that there are two forces here: the generative and the inducing.