瑜伽論記 10.371

10.371

義曰：若取意三參身口七即為十，若十者不成增數門，是以不取，前一切種門有六種七種，後二世樂有九門，今此遂求乘上來合增為八，故不取後意三以成十種也。

The meaning is: If one were to take the three mental [actions] to join with the seven bodily and verbal, that would make ten; if it were ten, it would not form an increasing-number approach, which is why they are not taken. The preceding approach of all kinds has six kinds and seven kinds, and the subsequent bliss of two lives has nine approaches; now this fulfilling of wishes builds upon what precedes and combines to increase to eight, hence it does not take the latter three mental [actions] to make ten kinds.