At first sight, what we see here is the very epitome of transitory reality: water, flowing over monolithic rock. The effervescent fluid is full of life and energy, and is demonstrably and obviously impermanent. The boulders are classic symbols of stability and permanence. But is either element really such a stalwart exemplar of the class of being that it purports to be?
Are not the rocks, if viewed in their natural context, more of an impermanent reality than the water, as they slowly, but inevitably, succumb to the rushing water's punishing power? Is not the flow of water (rather than its substance), in fact, a much longer living entity; one destined to outlive even the strongest of rocks? How many years had the "rocks" that are no longer part of the Grand Canyon withstood the inexorable onslaught of the Colorado River's persistent flow?...
...and what is the analog, I wonder, of the "rushing water" to our seemingly permanent (but, in truth, merely transitory) "reality" as living, sentient, and soulful creatures? How many years will go by before life itself becomes a distant memory? ...before it turns into an organically eroded gorge, carved into oblivion by the methodical, uncaring flow of time?
This existence of ours is as transient as autumn clouds
To watch the birth and death of beings is like looking at the movements of a dance.
A lifetime is like a flash of lightning in the sky,
Rushing by, like a torrent down a steep mountain. - Buddha