Rocks have a peculiar appeal to me. They're so, well, fundamental. To me, they symbolize steadfastness and solidity. And they contain a message.

The roundness and symmetry of this particular rock really say "solid." Since long before there was something called history, it has withstood the pressure and erosive effects of fast-moving water. To emphasize the quality of solidity, I placed the rock near the bottom-center of the image and showed the water flowing around both sides of it. The arrangement of other rocks, the forest and the downed trees in the background further reinforce this sense of solidity.

Rocks also speak volumes about "time," both time in the past and time in the future. Despite its extreme age and obvious solidity, this rock will eventually -- long after I'm gone -- succumb to the forces acting upon it, and be reduced to sand.

In this way, rocks tell us we must take a long view of life on Earth. Rocks tell us that life is not just the birds and trees and flowers we see around us, but that it is a system. While individual organisms may live only a short time, the system of life persists over eons. It is for this reason that we must live in a way that is sustainable. We must take responsibility to be conscientious stewards of nature. We must live in such a way as to not only satisfy our short-term needs and wants, but to sustain "the system" indefinitely. And that message is written in stone.