成唯識論述記 5.731

5.731

述曰：解第二句頌，於中有三：初釋六因；次隨別解；後顯不說。此即初也，六種差別至下當知。何以言六，更不分別為多或少？

The Commentary states: Explaining the second line of the verse, wherein there are three points: first, explaining the causes of the six; next, explaining each individually; and finally, clarifying what is not stated. This is the first: the six varieties will be understood below. Why are six stated, without further differentiation into more or fewer?