Patterns that Perpetuate Themselves

"We are but whirlpools in a river of ever-flowing water.  We are not stuff that abides, put patterns that perpetuate themselves."
-  Norbet Weiner, 1950

The human body is 60% water.   
The human body consists of about 60 trillion cells (6x10^13). 
There are about 60 trillion atoms in a human cell.   

"The structure of the human brain is enormously complex.  It contains about 10 billion nerve cells (neurons), which are interlinked in a vast network through 1,000 billion junctions (synapses).  The whole brain can be divided into subsections, or sub-networks, which communicate with each other in a network fashion.  All this results in intricate patterns of intertwined webs, networks of nesting within larger networks."
-  Fritjof Capra, The Web of Life: A New Scientific Understandinf of Living Systems, 1996, p. 82

"In opposition to the classical model of change as accidental (as by Aristotle) or illusory, process philosophy regards change as the cornerstone of reality—the cornerstone of the Being thought as Becoming. Modern philosophers who appeal to process rather than substance include Nietzsche, Heidegger, Charles Peirce, Alfred North Whitehead, Robert M. Pirsig, Charles Hartshorne, Arran Gare and Nicholas Rescher. In physics, Ilya Prigogine distinguishes between the "physics of being" and the "physics of becoming". Process philosophy covers not just scientific intuitions and experiences, but can be used as a conceptual bridge to facilitate discussions among religion, philosophy, and science."
-  Process Philosophy in Wikipedia

"Although people may think of their body as a fairly permanent structure, most of it is in a state of constant flux as old cells are discarded and new ones generated in their place. Each kind of tissue has its own turnover time, depending in part on the workload endured by its cells. The cells lining the stomach, as mentioned, last only five days. The red blood cells, bruised and battered after traveling nearly 1,000 miles through the maze of the body's circulatory system, last only 120 days or so on average before being dispatched to their graveyard in the spleen.  White blood cells live on average more than a year. 
The epidermis, or surface layer of the skin, is recycled every two weeks or so. The reason for the quick replacement is that "this is the body's saran wrap, and it can be easily damaged by scratching, solvents, wear and tear," said Elaine Fuchs, an expert on the skin's stem cells at the Rockefeller University.
As for the liver, the detoxifier of all the natural plant poisons and drugs that pass a person's lips, its life on the chemical-warfare front is quite short. An adult human liver probably has a turnover time of 300 to 500 days, said Markus Grompe, an expert on the liver's stem cells at the Oregon Health & Science University.
Other tissues have lifetimes measured in years, not days, but are still far from permanent. Even the bones endure nonstop makeover. The entire human skeleton is thought to be replaced every 10 years or so in adults, as twin construction crews of bone-dissolving and bone-rebuilding cells combine to remodel it.
About the only pieces of the body that last a lifetime, on present evidence, seem to be the neurons of the cerebral cortex, the inner lens cells of the eye and perhaps the muscle cells of the heart. The inner lens cells form in the embryo and then lapse into such inertness for the rest of their owner's lifetime that they dispense altogether with their nucleus and other cellular organelles."
-  Nicholas Wade, Your Body is Younger Than You Think

Complexity