In the forest, by the example of dead leaves,
Come to realize that the body, youth and senses
Change gradually and do not possess any true essence.
By the example of empty lotus ponds,
Come to realize that various objects of desire, wealth and prosperity
Are finally going to change, that there is no true essence in them;
And that what is accumulated will be exhausted.
By the example of the change of days, months and the four seasons,
Come to realize that the blossoming spring flower-like body
Is subject to change as time passes;
Its youth fades away; and the arrival of the lord of death is certain.
By the example of the fall of ripened fruit,
Come to realize that all young, adult or old
Are subject to die; that the time of death is uncertain; and that what is born will die.
By the example of the arising of reflections in ponds,
Come to realize that the various phenomena appear but have no true existence.
They are like illusions, a mirage, and a water moon,
And are certain to be empty of true existence.
(Teachings given by the great Dzogchen Master Longchen-pa, published in The Practice of Dzogchen.)