6.
The Discourse on Perception
16.
"Monks, these nine perceptions, when developed and cultivated, are of great fruit and great benefit, grounded upon the Deathless, having the Deathless as their final goal.
Which nine?
Perception of foulness, perception of death, perception of repulsiveness in food, perception of discontent with the whole world, perception of impermanence, perception of suffering in what is impermanent, perception of non-self in what is suffering, perception of abandoning, perception of dispassion -
these, monks, are the nine perceptions which, when developed and cultivated, are of great fruit and great benefit, grounded upon the Deathless, having the Deathless as their final goal."
The sixth.