Likewise, our bodies are also organized into groups for the convenience of the doctor. You can find a liver here, a stomach there, and a brain on top of everything else. Our (manmade) structure of the body makers it easier to learn and understand the body, but it’s important to remember that all these organ systems we’re going to talk about are the strategic use of our imaginations. I’m afraid their of no use to the philosophy of the origin of mankind.
This organizational structure forms a mental model of the body, and should be thought of as a system of systems. But before we go further, we should define a system, no this definition just didn’t appear here, but was rather manmade to facilitate a branch of study sometimes called systems thinking.
I want to share with you a story I was told in the beginning of med-school, it has helped my thinking throughout my career, and I hope you find it useful as well. The lecture was titled “Why the Universe is Organized into Hierarchies "– A Fable.
There once were two watchmakers, named Hora and Tempus. Both of them made fine watches, and they both had many customers. People dropped into their stores, and their phones rang constantly with new orders. Over the years, however, Hora prospered, while Tempus became poorer and poorer. That’s because Hora discovered the principle of hierarchy …
The watches made by both Hora and Tempus consisted of about one thousand parts each. Tempus put his together in such a way that if he had one partly assembled and had to put it down – answer the phone, say – it fell to pieces. When he came back to it, Tempus would have to start all over again. The more his customers phoned him the harder it became for him to find enough uninterrupted time to finish a watch.
Hora’s watches were no less complex than those of Tempus, but he put together stable subassemblies of about ten elements each. Then he put ten of these subassemblies together into a larger assembly; and ten of those assemblies constituted the whole watch. Whenever Hora had to put down a partly completed watch to answer the phone, he lost only a small part of his work. So he made his watches much faster and more efficiently than did Tempus.
Complex systems can evolve from simple systems only if there are stable intermediate forms. The resulting complex forms will naturally be hierarchic. That may explain why hierarchies are so common in the systems nature presents to us. Among all possible complex forms, hierarchies are the only ones that have time to evolve. Paraphrased from Herbert Simon.
Hierarchies are brilliant systems inventions, not only because they give a system stability and resilience, but also because they reduce the amount of information that any part of the system has to keep track of.
In hierarchical systems relationships within each subsystem are denser and stronger than relationships between subsystems. Everything is still connected to everything else, but not equally strongly. The cells that constitute the liver are in closer communication with each other than are the cells of the heart.
If you have liver disease, for example, a doctor usually can treat it without paying much attention to your heart or your tonsils (to stay on the same hieratical level) or your personality (to move up a level of hierarchy or two) or the DNA in the nuclei of the liver cells (to move down several levels). There are just enough exceptions to that rule, however, to reinforce the necessity of stepping back to consider the whole hierarchy.
So what is a system? A system just isn’t any old collection of things as found in the stars. It is an interconnected set of elements that is coherently organized in a way that achieves something. So from this definition, we can see that a system must have three things; elements, interconnections, and a function or purpose.
For example, your digestive system includes teeth, enzymes, stomach, and intestines. They are interrelated through the physical flow of food, and an elegant set of regulating chemical signals. The function of this system is to break down food into its basic nutrients and to transfer those nutrients into the bloodstream (another system) while discarding unusable wastes.
The human body contains trillions of cells, 78 different organs and more than 60,000 miles of blood vessels if you stretched them end-to-end. Incredibly, all of these cells, vessels and organs work together to keep you alive.
Each organ belongs to one of ten human body systems. These body systems are interconnected and dependent upon one another to function. Your heart does not beat unless your brain and nervous system tell it to do so. Your skeletal system relies on the nutrients it gains from your digestive system to build strong, healthy bones.
Working together, these systems maintain internal stability and balance, otherwise known as homeostasis. Disease in one body system can disrupt homeostasis and cause trouble in other body systems. If you become ill with the AIDS virus that affects your immune system, for example, you may develop pneumonia in your respiratory system, a yeast infection in your reproductive system, Candida that affects your esophagus in your digestive system or the skin cancer known as Kaposi’s sarcoma. The body’s systems help maintain a holistic balance to the marvelous system of systems we call the human body.
Organs of the body consist of specialized tissues that help them perform dedicated functions. These different tissues consist of cells of different types, and these cells consist of specialized cellular organelles. Each organelle performs a different function to help keep the cell, tissue, organ and body functioning properly through interconnections that keep the synergistic purpose greater than the sum of the parts. This is the system hierarchy that the Health Guardian manages to perform pathology prevention activities every day.