As I studied nursing this morning, I came across this incredible paragraph in my Medical-Surgical textbook:
“The amount of blood flow needed by body tissues constantly changes. The percentage of blood flow received by individual organs or tissues is determined by the rate of tissue metabolism, the availability of oxygen, and the function of the tissues…”
Smeltzer and Bare, Textbook of Medical-Surgical Nursing (11th Ed)
Perhaps this is an obvious fact to some, but as I paused to think, I found it amazing! The living tissues of the body are always changing, compensating, adjusting, fluctuating to the present situation. For example, when metabolic demands change with exercise, temperature change, infection, rest, etc., all of the different tissues of the body are constantly taking different amounts of oxygen from the blood.
This is how the body is different from a machine: every second, every tissue is adapting, changing, living. A machine is static, always the same, not adjusting.
In Wendell Berry’s words:
“Of course, the body in most ways is not at all like a machine. Like all living creatures and unlike a machine, the body is not formally self-contained; its boundaries and outlines are not so exactly fixed. The body alone is not, properly speaking, a body. Divided from its sources of air, food, drink, clothing, shelter, and companionship, a body is properly speaking, a cadaver, whereas a machine by itself, shut down or out of fuel, is still a machine Merely as an organism (leaving aside issues of mind and spirit) the body lives and moves and has its being, minute by minute, by an interinvolvement with other bodies and other creatures, living and unliving, that is too complex to diagram of describe. It is, moreover, under the influence of thought and feeling. It does not live by “fuel” alone.” (The Art of the Commonplace, “Health is Membership”)
The body is not like a machine because the body constantly responds to the environment. In a way, this makes the lines that mark where the body ends and the environment begins a little gray. The body reaches out into the environment, engaging it, adjusting to it (even down to the cellular level); whereas, a machine is isolated and self-contained.
Heather J K