The standard formula for the four noble truths—existence, origin, cessation, path—is applied to both dukkha and the āsavas. There is also a simile: Suppose in a mountain glen there were a lake with clear water, limpid and unsullied. A man with keen sight, standing on the bank, would see oyster-shells, sand and pebbles, and shoals of fish moving about and keeping still. He would think to himself: “This is a lake with clear water limpid and unsullied, and there within it are oyster-shells, sand and pebbles, and shoals of fish moving about and keeping still.” (DN 2.100)
