All sentient beings, without exception have buddha nature, the inherent purity and perfection of the mind, untouched by changing mental states. Thus there is neither any reason for conceit in deeming oneself better than others, nor any reason for self-contempt, thinking of oneself as inferior and unable to reach enlightenment. This seeing is obscured by veils which are removable and do not touch the inherent purity and perfection of the nature of the mind as such.
The Mahayana Uttaratantra Shastra, one of the "Five Treatises" said to have been dictated to Asanga by the Bodhisattva Maitreya, presents the Buddha's definitive teachings on how we should understand this ground of enlightenment and clarifies the nature and qualities of buddhahood. This seminal text clearly details the view which forms the basis for Vajrayana, and especially Mahamudra, practice. Thus it builds a bridge between the Sutrayana and Vajrayana levels of the Buddha's teaching, elaborated here in Jamgon Kongtrul's commentary.