rang bzhin ma 'gags rol pa'i klong

The Commentary on the Vajra Heart mentions that there are four Buddhist philosophical schools:

• The Buddhists have four schools:

A fifth is not the intent of Shakyamuni.

• Although the Hinayana has the two divisions of shravakas

and pratyekabuddhas, the view of the pratyekabuddhas is equivalent to the Saytrantika, while their resolve and conduct resembles the general system of shravakas. These points are therefore not mentioned separately. RY