If the mind is intrinsically pure, as maintained in the Śrimālādevi sūtra, the problem of defilement is a crucial one. To assert the purity of the mind yet also the impurity of the non—liberated state of mind, one must explain why the intrinsically pure nature of mind has been temporarily impeded by ignorance. The Śrimālādevi sūtra admits that the unaffected nature of mind which co—exists with defilement is difficult to comprehend. Momentariness is associated with activity, viz. a defiled or ignorant state and disassociated from the quiescent state of the intrinsically pure mind. The last impediment which stirs the mind from its original purity is referred to as the propensity of beginningless ignorance, which being non—momentary, is not active yet conditioned.