SELECT * FROM Celko – January 2014

The holidays are the usual mess. My refrigerator’s ice maker is dead and the dishwasher stopped working at the same time. The wife also decided that I needed to stain the deck just as Austin had a cold snap. In fairness, a cold snap here means that we actually see freezing weather. And we panic.
In all of this, I did get a chance to read a copy of THINKING IN SYSTEMS by Donella H. Meadows (ISBN: 978-1-60358-005-7). If you know her name, it would be for THE LIMITS TO GROWTH in 1972. This was a best-selling “doom and gloom” book that argued that unchecked consumption and economic growth would ‘overshoot’ the carrying capacity of the planet, and lead to disaster. There was an updated edition published in 2004; LIMITS TO GROWTH: THE 30 YEAR UPDATE (ISBN 978-1931498586) and it had some tweaks to their models.
Unfortunately, the new book does not contain the equations or even the parameters used! You had to fork over $1900 to get a CD with a modeling package named Stella and then you cannot change any of the model parameters or even to view them. One reviewer got a 30 day free trial version of Stella and extracted the equation in text form. A good job of detective work, but why make it that hard. 
The original book is full of problems. They made the assumption that populations and economies have exponential growth but that technology does not (Moore’s Law anyone?). They predicted a world population of seven billion by 2002, but the birth rates slowed. Predicted shortages of minerals and other resources never happened. In fact, many of those commodities are more plentiful than before. Perhaps the worst predictions were for the GDP of rich countries to continue to grow faster than Asia. Just read anything on China and India. 
Having just shot LIMITS TO GROWTH, you are probably expecting me to blast THINKING IN SYSTEMS but I am not. It is actually quite good! I have read books on General Systems Theory before, but most of them were full of calculus (differential equations for flow) and were abstract to the point of boring even a math geek. 
The opening chapter begins with a Slinky. Why does a Slinky bounce up and down, pour from hand to hand or walk down a staircase? It actions are not created by the hands that hold it. And the stairs are completely passive. The behavior and the feeling of amusement in watching a Slinky on the stairs is in the Slinky itself. While it might give you a warm, happy feeling to push some co-workers down a flight of stairs, they will not have the same behavior. 
“I have yet to see a problem, however complicated, which, when looked at the right way did not become still more complicated.” – Poul Anderson
She begins with three things that a system must have; elements, interconnections and a purpose. For example, a football team is made up of players, coaches, balls, playing fields, etc. They are connected by rules of the game, coaching strategy, etc. The purpose is to win games, get exercise, provide a social structure or make a ton of money if it is college and professional football.
The first principle is that a system is more that a collection of parts. I can identify the parts and what they do but the parts working together produce an effect that none of the parts could produce by themselves. 
Right now, we are looking at the train wreck known as Obamacare. One of its fundamental problems is that it is a collection of parts and not a system. The front end cannot connect to a back end to complete its task. 
The next big concept is that of stock. The water behind a dam is its stock, the minerals in a mine are its stock, inventory in a business is its stock and so forth. The quantity of stock will change with inputs and outputs. 
If too much stock comes in, water will overflow the dam or the inventory will pile up in the warehouse and choke the loading dock. 
If too much stock comes out, you have a drought or you get shortages in the inventory, lose orders and stop making money. 
This leads to the next concept; feedback loops! This is where most General Systems books jump into calculus and lose their readers. Ms. Meadows has graphs and formulas at this point, but depends on narratives. The one strong point she makes in a sidebar is usually not made clear in other books:
In physical, exponentially growing systems, there must be at least one reinforcing loop driving the growth and at least one balancing loop constraining the growth, because no physical system can grow forever in a finite environment. 
The rest of the book gets into renewable and non-renewable stock, resilience and self-organization. But Chapter five is on system traps. These are systems in which the feedback mechanisms lead to destructive situations. Imagine two idiots trying to play their radios louder than the other guy to drown out their opponent. 
The book is a good quick read and has more concepts. It is worth picking up. 

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About Joe Celko

Joe is an Independent SQL and RDBMS Expert. He joined the ANSI X3H2 Database Standards Committee in 1987 and helped write the ANSI/ISO SQL-89 and SQL-92 standards. He is one of the top SQL experts in the world, writing over 700 articles primarily on SQL and database topics in the computer trade and academic press. The author of six books on databases and SQL, Joe also contributes his time as a speaker and instructor at universities, trade conferences and local user groups. Joe is now an independent contractor based in the Austin, TX area.

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