Thinking in Systems
Thinking in Systems

Thinking in Systems

But the least obvious part of the system, its function or purpose, is often the most crucial determinant of the system’s behavior. (Location 445)

And conversely, because land, factories, and people are long-lived, slowly changing, physical elements of the system, there is a limit to the rate at which any leader can turn the direction of a nation. (Location 452)

A stock is the foundation of any system. Stocks are the elements of the system that you can see, feel, count, or measure at any given time. A system stock is just what it sounds like: a store, a quantity, an accumulation of material or information that has built up over time. (Location 460)

The human mind seems to focus more easily on stocks than on flows. On top of that, when we do focus on flows, we tend to focus on inflows more easily than on outflows. (Location 525)

It seems to be harder to understand that the same result can be achieved by burning less oil. (Location 528)

A stock can be increased by decreasing its outflow rate as well as by increasing its inflow rate. There’s more than one way to fill a bathtub! (Location 531)

These two strategies may have very different costs. (Location 534)

It also can be boosted, often more cheaply, by decreasing the rate at which factories and machines wear out, break down, or are discarded. (Location 535)

but it is much more difficult to change the level of water—the stock—quickly. (Location 537)

A stock takes time to change, because flows take time to flow. (Location 539)

Stocks usually change slowly. They can act as delays, lags, buffers, ballast, and sources of momentum in a system. Stocks, especially large ones, respond to change, even sudden change, only by gradual filling or emptying. (Location 540)

Stocks generally change slowly, even when the flows into or out of them change suddenly. Therefore, stocks act as delays or buffers or shock absorbers in systems. (Location 542)

takes a long time for populations to grow or stop growing, for wood to accumulate in a forest, for a reservoir to fill up, for a mine to be depleted. (Location 544)

Changes in stocks set the pace of the dynamics of systems. Industrialization cannot proceed faster than the rate at which factories and machines can be constructed and the rate at which human beings can be educated to run and maintain them. Forests can’t grow overnight. Once contaminants have accumulated in groundwater, they can be washed out only at the rate of groundwater turnover, which may take decades or even centuries. (Location 549)

The time lags imposed by stocks allow room to maneuver, to experiment, and to revise policies that aren’t working. (Location 555)

You can use the opportunities presented by a system’s momentum to guide it toward a good outcome—much as a judo expert uses the momentum of an opponent to achieve his or her own goals. (Location 558)

Stocks allow inflows and outflows to be decoupled and to be independent and temporarily out of balance with each other. (Location 562)

Banks enable you temporarily to earn money at a rate different from how you spend. Inventories of products along a chain from distributors to wholesalers to retailers allow production to proceed smoothly although customer demand varies, and allow customer demand to be filled even though production rates vary. (Location 569)

Most individual and institutional decisions are designed to regulate the levels in stocks. (Location 572)

Systems thinkers see the world as a collection of stocks along with the mechanisms for regulating the levels in the stocks by manipulating flows. (Location 580)

In other words, if you see a behavior that persists over time, there is likely a mechanism creating that consistent behavior. (Location 590)

A feedback loop is formed when changes in a stock affect the flows into or out of that same stock. A feedback loop can be quite simple and direct. (Location 592)

inflow). This kind of feedback loop is keeping your level of cash available within a range that is acceptable to you. You can see that adjusting your earnings is not the only feedback loop that works on your stock of cash. You also may be able to adjust the outflow of money from your account, for example. You can imagine an outflow-adjusting feedback loop for spending. (Location 600)

A feedback loop is a closed chain of causal connections from a stock, through a set of decisions or rules or physical laws or actions that are dependent on the level of the stock, and back again through a flow to change the stock. (Location 613)

but it does stay within an acceptable range. (Location 618)

This kind of stabilizing, goal-seeking, regulating loop is called a balancing feedback loop, so I put a B inside the loop in the diagram. (Location 639)

Balancing feedback loops are equilibrating or goal-seeking structures in systems and are both sources of stability (Location 660)

Reinforcing loops are found wherever a system element has the ability to reproduce itself or to grow as a constant fraction of itself. (Location 690)

I’ll leave it to you to decide whether you think these are actually decisions made with no feedback involved. (Location 714)

The information delivered by a feedback loop can only affect future behavior; (Location 801)

The information delivered by a feedback loop—even nonphysical feedback—can only affect future behavior; it can’t deliver a signal fast enough to correct behavior that drove the current feedback. Even nonphysical information takes time to feedback into the system. (Location 805)

A stock-maintaining balancing feedback loop must have its goal set appropriately to compensate for draining or inflowing processes that affect that stock. Otherwise, the feedback process will fall short of or exceed the target for the stock. (Location 820)

Complex behaviors of systems often arise as the relative strengths of feedback loops shift, causing first one loop and then another to dominate behavior. (Location 884)

System dynamics models explore possible futures and ask “what if” questions. (Location 921)

At the heart of the economy is another reinforcing-loop-plus-balancing- loop system—the same kind of structure, with the same kinds of behavior, as the population (see (Location 940)

With a relatively short lifetime, the capital wears out faster than it is replaced. (Location 963)

This is another example of a principle we’ve already encountered: You can make a stock grow by decreasing its outflow rate as well as by increasing its inflow rate! (Location 966)

In a system with output per unit capital ratio of 1:3 and an investment fraction of 20 percent, capital with a lifetime of 15 years just keeps up with depreciation. A shorter lifetime leads to a declining stock of capital. (Location 974)

A production system with factories and shipments and economic flows doesn’t look much like a population system with babies being born and people aging and having more babies and dying. (Location 980)

their feedback-loop structures. (Location 982)

Systems with similar feedback structures produce similar dynamic behaviors. (Location 985)

Oscillations! A single step up in sales causes inventory to drop. The car dealer watches long enough to be sure the higher sales rate is going to last. (Location 1024)

A delay in a balancing feedback loop makes a system likely to oscillate. (Location 1040)

Delays are pervasive in systems, and they are strong determinants of behavior. (Location 1069)

Changing the length of a delay may (or may not, depending on the type of delay and the relative lengths of other (Location 1070)

delays) make a large change in the behavior of a system. (Location 1070)

But imagine that the inventory is that of all the unsold automobiles in America. Orders for more or fewer cars affect production not only at assembly plants and parts factories, but also at steel mills, rubber and glass plants, textile producers, and energy producers. (Location 1081)

The capital stock of the industrial economy model didn’t require raw materials to produce output. The (Location 1095)

Therefore, any physical, growing system is going to run into some kind of constraint, sooner or later. (Location 1103)

Growth in a constrained environment is very common, so common that systems thinkers call it the “limits-to-growth” archetype. (We’ll explore more archetypes—frequently found system structures that produce familiar behavior patterns—in Chapter Five.) (Location 1105)

we look for the reinforcing loops that are driving it and for the balancing loops that ultimately will constrain it. (Location 1108)

Even a hot new product will saturate the market eventually. (Location 1110)

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. (Location 1113)

Driving depreciation is the now-familiar balancing loop: the more capital stock, the more machines and refineries there are that fall apart and wear out, reducing the stock of capital. (Location 1127)

More capital allows more resource extraction, creating more profits that can be reinvested. I’ve assumed that the company has a goal of 5 percent annual growth in its business capital. (Location 1131)

Here is a new balancing feedback loop that ultimately will control the growth of capital: the more capital, the higher the extraction rate. (Location 1142)

The lower the resource stock, the lower the yield of resource per unit of capital, so the lower the profit (with price assumed constant) and the lower the investment rate—therefore, the lower the rate of growth of capital. (Location 1144)

A quantity growing exponentially toward a constraint or limit reaches that limit in a surprisingly short time. (Location 1166)

This same “renewable resource system” structure occurs in an epidemic of a cold virus. It spares its victims who are then able to catch another cold. Sales (Location 1212)

The first is the critical threshold beyond which the resource population’s ability to regenerate itself is damaged. (Location 1287)

The second is the rapidity and effectiveness of the balancing feedback loop that slows capital growth as the resource becomes depleted. (Location 1288)

If the balancing feedback is slower and less effective, the system oscillates. If the balancing loop is very weak, so that capital can go on growing even as the resource is reduced below its threshold ability to regenerate itself, the resource and the industry both collapse. (Location 1290)

Chapter Two introduced simple systems that create their own behavior based on their structures. (Location 1306)

If pushed too far, systems may well fall apart or exhibit heretofore unobserved behavior. (Location 1310)

“the ability to bounce or spring back into shape, position, etc., after being pressed or stretched. (Location 1321)

system’s ability to survive and persist within a variable environment. (Location 1323)

A set of feedback loops that can restore or rebuild feedback loops is resilience at a still higher level—meta-resilience, if you will. (Location 1327)

that can learn, create, design, and evolve ever more complex restorative structures. (Location 1329)

multiplying or declining over time in response to weather and the availability of nutrients and the impacts of human activities. (Location 1338)

They can, given enough time, come up with whole new systems to take advantage of changing opportunities for life support. (Location 1340)

And, conversely, systems that are constant over time can be unresilient. (Location 1344)

Because resilience may not be obvious without a whole-system view, people often sacrifice resilience for stability, or for productivity, or for some other more immediately recognizable system property. (Location 1347)

The cost of increased production is lowered resilience. The cow is less healthy, less long-lived, more dependent on human management. (Location 1351)

The just-in-time model also has made the production system more vulnerable, however, to perturbations in fuel supply, traffic flow, computer breakdown, labor availability, and other possible glitches. (Location 1354)

these forests have lost their resilience. They seem to be especially vulnerable to a new form of insult: industrial air pollution. (Location 1358)

Ecological disasters in many places come from loss of resilience, as species are removed from ecosystems, soil chemistry and biology are disturbed, or toxins build up. (Location 1361)

lose their resilience simply because the feedback mechanisms by which they sense and respond to their environment have (Location 1363)

As a system loses its resilience, its plateau shrinks, and its protective walls become lower and more rigid, until the system is operating on a knife edge, likely to fall off in one direction or another whenever it makes a move. (Location 1367)

Systems need to be managed not only for productivity or stability, they also need to be managed for resilience—the ability to recover from perturbation, the ability to restore or repair themselves. (Location 1370)

You see self-organization in a more profound way whenever a seed sprouts, or a baby learns to speak, or a neighborhood decides to come together to oppose a toxic waste dump. (Location 1389)

Self-organization produces heterogeneity and unpredictability. It is likely come up with whole new structures, whole new ways of doing things. (Location 1397)

Fortunately, self-organization is such a basic property of living systems that even the most overbearing power structure can never fully kill it, (Location 1402)

Systems often have the property of self-organization—the ability to structure themselves, to create new structure, to learn, diversify, and complexify. Even complex forms of self-organization may arise from relatively simple organizing rules—or may not. (Location 1430)

Science, itself a self-organizing system, likes to think that all the complexity of the world must arise, ultimately, from simple rules. (Location 1433)

The world, or at least the parts of it humans think they understand, is organized in subsystems aggregated into larger subsystems, aggregated into still larger subsystems. (Location 1444)

If subsystems can largely take care of themselves, regulate themselves, maintain themselves, and yet serve the needs of the larger system, while the larger system coordinates and enhances the functioning of the subsystems, a stable, resilient, and efficient structure results. (Location 1449)

In hierarchical systems relationships within each subsystem are denser and stronger than relationships between subsystems. (Location 1469)

Hierarchical systems are partially decomposable. (Location 1474)

When hierarchies break down, they usually split along their subsystem boundaries. (Location 1475)

However, one should not lose sight of the important relationships that each subsystem to the others and to the higher levels of the hierarchy, or one will be in for surprises. (Location 1478)

The original purpose of a hierarchy is always to help its originating subsystems do their jobs better. (Location 1493)

When a subsystem’s goals dominate at the expense of the total system’s goals, the resulting behavior is called suboptimization. (Location 1500)

of course, is the problem of too much central control. (Location 1502)

To be a highly functional system, hierarchy must balance the welfare, freedoms, and responsibilities of the subsystems and total system— (Location 1506)

That you and I are surprised says as much about us as it does about dynamic systems. (Location 1523)

Everything we think we know about the world is a model. (Location 1525)

Our models usually have a strong congruence with the world. (Location 1528)

However, and conversely, our models fall far short of representing the world fully. (Location 1531)

We often draw illogical conclusions from accurate assumptions, or logical conclusions from inaccurate assumptions. (Location 1532)

We are less likely to be surprised if we can see how events accumulate into dynamic patterns of behavior. (Location 1570)

The behavior of a system is its performance over time—its growth, stagnation, decline, oscillation, randomness, or evolution. (Location 1573)

That’s because long term behavior provides clues to the underlying system structure. And structure is the key to understanding not just what is happening, but why. (Location 1576)

The structure of a system is its interlocking stocks, flows, and feedback loops. The diagrams with boxes and arrows (my students call them “spaghetti-and-meatball diagrams”) (Location 1578)

what behaviors are latent in the system. A goal-seeking balancing feedback loop approaches or holds a dynamic equilibrium. (Location 1580)

A reinforcing feedback loop generates exponential growth. The two of them linked together are capable of growth, decay, or equilibrium. (Location 1580)

System structure is the source of system behavior. System behavior reveals itself as a series of events over time. (Location 1583)

Systems thinking goes back and forth constantly between structure (diagrams of stocks, flows, and feedback) and behavior (time graphs). Systems thinkers strive to understand the connections between the hand releasing the Slinky (event) and the resulting oscillations (behavior) and the mechanical characteristics of the Slinky’s helical coil (structure). (Location 1585)

Systems thinkers strive to understand the connections between the hand releasing the Slinky (event) and the resulting oscillations (behavior) and the mechanical characteristics of the Slinky’s helical coil (structure). (Location 1586)

They give you no ability to change the behavior of the system—to make the stock market less volatile or a more reliable indicator of the health of corporations or a better vehicle to encourage investment, for instance. (Location 1592)

These behavior-based models are more useful than event-based ones, but they still have fundamental problems. First, they typically overemphasize system flows and underemphasize stocks. (Location 1596)

First, they typically overemphasize system flows and underemphasize stocks. (Location 1597)

Economic news reports on the national production (flow) of goods and services, the GNP, rather than the total physical capital (stock) of the nation’s factories and farms and businesses that produce those goods and services. (Location 1598)

Second, and more seriously, in trying to find statistical links that relate flows to each other, econometricians are searching for something that does not exist. (Location 1601)

There’s no reason to expect any flow to bear a stable relationship to any other flow. Flows go up and down, on and off, in all sorts of combinations, in response to stocks, not to other flows. (Location 1603)

Flows go up and down, on and off, in all sorts of combinations, in response to stocks, not to other flows. (Location 1603)

only until something changes in the system’s structure—someone opens a window or improves the insulation, or tunes the furnace, or forgets to order oil. (Location 1608)

You could predict tomorrow’s room temperature with your equation, as long as the system didn’t change or break down. (Location 1609)

A nonlinear relationship is one in which the cause does not produce a proportional effect. (Location 1628)

If we’ve learned that a small push produces a small response, we think that twice as big a push will produce twice as big a response. (Location 1633)

They are even more important because they change the relative strengths of feedback loops. They can flip a system from one mode of behavior to another. (Location 1648)

sudden swing between exponential growth caused by a dominant reinforcing loop, say, and then decline caused by a suddenly dominant balancing loop. (Location 1650)

As the fir population builds up, the probability of an outbreak increases—nonlinearly. (Location 1673)

The reinforcing loop of budworm reproduction yields dominance to the balancing loop of budworm starvation. Spruce and birch move into the spaces where the firs used to be, and the cycle begins again. (Location 1682)

Many relationships in systems are nonlinear. Their relative strengths shift in disproportionate amounts as the stocks in the system shift. Nonlinearities in feedback systems produce shifting dominance of loops and many complexities in system behavior. (Location 1688)

Clouds stand for the beginnings and ends of flows. They are stocks—sources and sinks—that are being ignored at the moment for the purposes of simplifying the present discussion. (Location 1705)

The greatest complexities arise exactly at boundaries. (Location 1710)

In our system zoo, for instance, I showed the flow of cars into a car dealer’s inventory as coming from a cloud. Of course, cars don’t come from a cloud, they come from the transformation of a stock of raw materials, with the help of capital, labor, energy, technology, and management (the means of production). Similarly, the flow of cars out of the inventory goes not to a cloud, but through sales to the households or businesses of consumers. (Location 1712)

the long term, the full flow is important and, as the physical economy grows and society’s “ecological footprint” expands, the long term is increasingly coming to be the short term. (Location 1728)

Sources of raw materials—mines, wells, and oil fields—can be exhausted with surprising suddenness too. (Location 1731)

With a long enough time horizon, even mines and dumps are not the end of the story. The great geological cycles of the earth keep moving materials around, opening and closing seas, raising up and wearing down mountains. (Location 1732)

There are no separate systems. The world is a continuum. Where to draw a boundary around a system depends on the purpose of the discussion—the questions we want to ask. (Location 1747)

When you draw boundaries too narrowly, the system surprises you. For example, if you try to deal with urban traffic problems without thinking about settlement patterns, you build highways, which attract housing developments along their whole length. Those households, in turn, put more cars on the highways, which then become just as clogged as before. (Location 1750)

Systems analysts often fall into the opposite trap: making boundaries too large. (Location 1759)

For example, modeling the earth’s climate in full detail is interesting for many reasons, but may not be necessary for figuring out how to reduce a country’s CO2 emissions to reduce climate change. (Location 1763)

The right boundary for thinking about a problem rarely coincides with the boundary of an academic discipline, or with a political boundary. (Location 1765)

Ideally, we would have the mental flexibility to find the appropriate boundary for thinking about each new problem. We are rarely that flexible. (Location 1769)

We are rarely that flexible. We get attached to the boundaries our minds happen to be accustomed to. (Location 1770)

It’s a great art to remember that boundaries are of our own making, and that they can and should be reconsidered for each new discussion, problem, or purpose. (Location 1780)

Multiple inputs produce multiple outputs, and virtually all of the inputs, and therefore outputs, are limited. (Location 1787)

This concept of a limiting factor is simple and widely misunderstood. Agronomists assume, for example, that they know what to put in artificial fertilizer, because they have identified many of the major and minor nutrients in good soil. Are there any essential nutrients they have not identified? How do artificial fertilizers affect soil microbe communities? Do they interfere with, and therefore limit, any other functions of good soil? And what limits the production of artificial fertilizers? (Location 1818)

At any given time, the input that is most important to a system is the one that is most limiting. (Location 1822)

wonder why the economies of the receiving countries still don’t develop, never thinking that capital or technology may not be the most limiting factors. (Location 1824)

As the economy grows relative to the ecosystem, however, and the limiting factors shift to clean water, clean air, dump space, and acceptable forms of energy and raw materials, the traditional focus on only capital and labor becomes increasingly unhelpful. (Location 1827)

The problem for this company is to recognize deal with its shifting limits—limits that change in response to the company’s own growth. (Location 1830)

Insight comes not only from recognizing which factor is limiting, but from seeing that growth itself depletes or enhances limits and therefore changes what is limiting. (Location 1837)

Whenever one factor ceases to be limiting, growth occurs, and the growth itself changes the relative scarcity of factors until another becomes limiting. To shift attention from the abundant factors to the (Location 1839)

For any physical entity in a finite environment, perpetual growth is impossible. (Location 1845)

Any physical entity with multiple inputs and outputs is surrounded by layers of limits. (Location 1851)

If they aren’t, they will be system-imposed. No physical entity can grow forever. If company managers, city governments, the human population do not choose and enforce their own limits to keep growth within the capacity of the supporting environment, then the environment will choose and enforce limits. (Location 1852)

No physical entity can grow forever. If company managers, city governments, the human population do not choose and enforce their own limits to keep growth within the capacity of the supporting environment, then the environment will choose and enforce limits. (Location 1853)

Delays are ubiquitous in systems. Every stock is a delay. Most flows have delays—shipping delays, perception delays, processing delays, maturation Here are just a few of the delays we have found important to include in various models we have made: (Location 1870)

Delays determine how fast systems can react, how accurately they hit their targets, and how timely is the information passed around a system. (Location 1892)

Overshoots, oscillations, and collapses are always caused by delays. (Location 1893)

When there are long delays in feedback loops, some sort of foresight is essential. To act only when a problem becomes obvious is to miss an important opportunity to solve the problem. (Location 1900)

Tourists flock to places like Waikiki or Zermatt and then complain that those places have been ruined by all the tourists. (Location 1914)

Corporations collectively make investment decisions that cause business-cycle downturns. (Location 1916)

Bounded rationality means that people make quite reasonable decisions based on the information they have. But they don’t have perfect information, especially about more distant parts of the system. Fishermen don’t know how many fish there are, much less how many fish will be caught by other fishermen that same day. (Location 1920)

We are not omniscient, rational optimizers, says Simon. Rather, we are blundering “satisficers,” attempting to meet (satisfy) our needs well enough (sufficiently) before moving on to the next decision. (Location 1926)

So instead of finding a long term optimum, we discover within our limited purview a choice we can live with for now, (Location 1931)

We don’t even interpret perfectly the imperfect information that we do have, say behavioral scientists. We misperceive risk, assuming that some things are much more dangerous than they really are and others much less. (Location 1932)

We misperceive risk, assuming that some things are much more dangerous than they really are and others much less. We live in an exaggerated present—we pay too much (Location 1933)

focusing on current events rather than long term behavior. (Location 1935)

weights. We don’t let in at all news we don’t like, or information that doesn’t fit our mental models. Which is to say, we don’t even make decisions that optimize our own individual good, much less the good of the system as a whole. (Location 1936)

Suppose you are for some reason lifted out of your accustomed place in society and put in the place of someone whose behavior you have never understood. (Location 1946)

In your new position, you experience the information flows, the incentives and disincentives, the goals and discrepancies, the pressures—the bounded rationality—that goes with that position. (Location 1950)

If you become a financier, you probably will overinvest during booms and underinvest during busts, along with all the other financiers. (Location 1954)

We teach this point by playing games in which students are put into situations in which they experience the realistic, partial information streams seen by various actors in real systems. (Location 1957)

Change comes first from stepping outside the limited information that can be seen from any single place in the system and getting an overview. (Location 1966)

Some systems are structured to function well despite bounded rationality. The (Location 1983)

In some ways, it is. In other ways, obvious to anyone who is willing to look, it isn’t. A free market does allow producers and consumers, who have the best information about production opportunities and consumption choices, to make fairly uninhibited and locally rational decisions. (Location 1988)

correct the overall system’s tendency to create monopolies and undesirable side effects (externalities), to discriminate against the poor, or to overshoot its sustainable carrying capacity. (Location 1990)

The bounded rationality of each actor in a system may not lead to decisions that further the welfare of the system as a whole. (Location 1999)

They have a common underlying concern: how to get their particular system to function. Meanwhile . . . civilization becomes increasingly directionless and incomprehensible. (Location 2005)

Generally, they are not properties that can or should be changed. The world is nonlinear. Trying to make it linear for our mathematical or administrative convenience is not usually a good idea even when feasible, and it is rarely feasible. (Location 2010)

Being less surprised by complex systems is mainly a matter of learning to expect, appreciate, and use the world’s complexity. (Location 2013)

We call the system structures that produce such common patterns of problematic behavior archetypes. (Location 2016)

As we saw in Chapter Two, the primary symptom of a balancing feedback loop structure is that not much changes, despite outside forces pushing the system. Balancing loops stabilize systems; behavior patterns persist. (Location 2033)

There are wars on drugs, after which drugs are as prevalent as ever. There is little evidence that investment tax credits and many other policies designed to stimulate investment when the market is not rewarding investment actually work. (Location 2038)

Picture a single-system stock—drug supply on the city streets, for example—with various actors trying to pull that stock in different directions. (Location 2047)

In a policy-resistant system with actors pulling in different directions, everyone has to put great effort into keeping the system where no one wants it to (Location 2055)

Intensification of anyone’s effort leads to intensification of everyone else’s. It’s hard to reduce intensification. It takes a lot of mutual trust to say, OK, why don’t we all just back off for a while? (Location 2057)

Although contraceptives and abortions remained illegal, the birth rate slowly came back down nearly to its previous level. This result was achieved primarily though dangerous, illegal abortions, which tripled the maternal mortality rate. (Location 2062)

Romanian families were too poor to raise the many children their government desired decently, and they knew it. (Location 2064)

If you wield enough power and can keep wielding it, the power approach can work, at the cost of monumental resentment and the possibility of explosive consequences if the power is ever let up. This is what happened with the formulator of the Romanian population policy, dictator Nicolae Ceausescu, who tried long and hard to overpower the resistance to his policy. (Location 2067)

Give up ineffective policies. Let the resources and energy spent on both enforcing and resisting be used for more constructive purposes. (Location 2072)

Let the resources and energy spent on both enforcing and resisting be used for more constructive purposes. You won’t get your way with the system, but it won’t go as far in a bad direction as you think, because much of the action you were trying to correct was in response to your own action. If you calm down, those who are pulling against you will calm down too. (Location 2072)

If everyone can work harmoniously toward the same outcome (if all feedback loops are serving the same goal), the results can be amazing. (Location 2086)

The trap called the tragedy of the commons comes about when there is escalation, or just simple growth, in a commonly shared, erodable environment. (Location 2113)

In any commons system there is, first of all, a resource that is commonly shared (the pasture). (Location 2126)

the less resource there is, the less it is able to regenerate itself, or the more likely it is to be destroyed. (Location 2128)

The tragedy of the commons arises from missing (or too long delayed) feedback from the resource to the growth of the users of that resource. (Location 2137)

Privatization works more reliably than exhortation, if society is willing to let some individuals learn the hard way. But many resources, such as the atmosphere and the fish of the sea, simply cannot be privatized. That leaves only the option of “mutual coercion, mutually agreed upon.” (Location 2178)

Some systems not only resist policy and stay in a normal bad state, they keep getting worse. (Location 2220)

worse. One name for this archetype is “drift to low performance.” (Location 2221)

The actor in this feedback loop (British government, business, hospital, fat person, school administrator, jogger) has, as usual, a performance goal or desired system state that is compared to the actual state. (Location 2223)

The actor tends to believe bad news more than good news. As actual performance varies, the best results are dismissed as aberrations, the worst results stay in the memory. The actor thinks things are worse than they really (Location 2227)

There are two antidotes to eroding goals. One is to keep standards absolute, regardless of performance. Another is to make goals sensitive to the best performances of the past, instead of the worst. (Location 2242)

One is to keep standards absolute, regardless of performance. Another is to make goals sensitive to the best performances of the past, instead of the worst. (Location 2243)

Escalation comes from a reinforcing loop set up by competing actors trying to get ahead of each other. (Location 2265)

that market competition systematically eliminates market competition—is demonstrated wherever there is, or used to be, a competitive market. (Location 2341)

most major U.S. cities, there is only one newspaper left. In every market economy, we see long term trends of declining numbers of farms, while the size of farms increases. (Location 2343)

Species and companies sometimes escape competitive exclusion by diversifying. (Location 2361)

A species can learn or evolve to exploit new resources. (Location 2361)

Markets tend toward monopoly and ecological niches toward monotony, but they also create offshoots of diversity, new markets, new species, which in the course of time may attract competitors, which then begin to move the system toward competitive exclusion again. (Location 2362)

The success-to the-successful loop can be kept under control by putting into place feedback loops that keep any competitor from taking over entirely. (Location 2367)

Monopoly games start over again with everyone equal, so those who lost last time have a chance to win. (Location 2372)

Most industrial societies have some combination of checks like these on the workings of the success-to- the-successful trap, (Location 2377)

if they are unable to get out of the game of success to the successful, and if they have no hope of winning, could get frustrated enough to destroy the playing field. (Location 2380)

If the winners of a competition are systematically rewarded with the means to win again, a reinforcing feedback loop is created by which, if it is allowed to proceed uninhibited, the winners eventually take all, while the losers are eliminated. (Location 2383)

Diversification, which allows those who are losing the competition to get out of that game and start another one; (Location 2386)

removing some of the advantage of the strongest players or increasing the advantage of the weakest; (Location 2388)

such as the dependence of industry on government subsidy, the reliance of farmers on fertilizers, the addiction of Western economies to cheap oil or weapons manufacturers to government contracts. (Location 2406)

The structure includes a stock with in-flows and out-flows. The stock can be physical (a crop of corn) or meta-physical (Location 2408)

But the drugs quickly alter your perception of your state, numbing your senses and making you feel tireless and brave. (Location 2414)

company, and if you can get the government to subsidize you, you can go on making money and continue to have a good profit, thereby remaining a respected member of society. (Location 2416)

The trouble is that the states created by interventions don’t last. The intoxication wears off. The subsidy is spent. The fertilizer is consumed or washed away. (Location 2419)

It often is done purposefully, and the result can be an increased ability to keep the system in a desirable state. Surely the 100 percent protection from smallpox vaccines, if it lasts, is preferable to only partial protection from natural smallpox immunity. (Location 2431)

A corrective feedback process within the system is doing a poor (or even so-so) job of maintaining the state of the system. (Location 2434)

A well-meaning and efficient intervenor watches the struggle and steps in to take some of the load. (Location 2435)

The intervenor quickly brings the system to the state everybody wants it to be in. Congratulations are in order, usually self-congratulations (Location 2436)

Then the original problem reappears, since nothing has been done to solve it at its root cause. So the intervenor applies more of the “solution,” disguising the real state of the system again, and thereby failing to act on the problem. That makes it necessary to use still more “solution.” (Location 2437)

The trap is formed if the intervention, whether by active destruction or simple neglect, undermines the original capacity of the system to maintain itself. (Location 2440)

Why does anyone enter the trap? First, the intervenor may not foresee that the initial urge to help out a bit can start a chain of events that leads to ever-increasing dependency, which ultimately will strain the capacity of the intervenor. The American health-care system is experiencing the strains of that sequence of events. (Location 2443)

First, the intervenor may not foresee that the initial urge to help out a bit can start a chain of events that leads to ever-increasing dependency, which (Location 2443)

Second, the individual or community that is being helped may not think through the long term loss of control and the increased vulnerability that go along with the opportunity to shift a burden to an able and powerful intervenor. (Location 2446)

If the intervention is a drug, (Location 2448)

the symptom of the problem, which prevents or distracts one from the harder and longer-term task of solving the real problem. (Location 2451)

That will make the bugs go away, and allow more monocultures, more destruction of ecosystems. That will bring back the bugs in greater outbursts, requiring more pesticides in the future. (Location 2454)

That way we can pretend that nothing is happening and go on burning oil—making the depletion problem worse. (Location 2458)

Withdrawal means finally confronting the real (and usually much deteriorated) state of the system and taking the actions that the addiction allowed one to put off. (Location 2463)

Sometimes a nonaddictive policy can be put in place first to restore the degraded system with a minimum of turbulence (Location 2464)

pests). Sometimes there’s no way out but to go cold turkey and just bear the pain. It’s worth going through the withdrawal to get back to an unaddicted state, but it is far preferable to avoid addiction in the first place. (Location 2466)

The problem can be avoided up front by intervening in such a way as to strengthen the ability of the system to shoulder its own burdens. (Location 2469)

in such a way as to strengthen the ability of the system to shoulder its own burdens. This option, helping the system to help itself, can be much cheaper and easier than taking over and running the system—something liberal politicians don’t seem to understand. (Location 2469)

Shifting the burden, dependence, and addiction arise when a solution to a systemic problem reduces (or disguises) the symptoms, (Location 2476)

If the intervention designed to correct the problem causes the self-maintaining capacity of the original system to atrophy or erode, then a destructive reinforcing feedback loop is set in motion. (Location 2479)

If you are the one with an unsupportable dependency, build your system’s own capabilities back up before removing the intervention. (Location 2487)

law. Rule beating becomes a problem only when it leads a system into large distortions, unnatural behaviors that would make no sense at all in the absence of the rules. If it gets out of hand, rule beating can cause systems to produce very damaging behavior indeed. (Location 2498)

Rule beating becomes a problem only when it leads a system into large distortions, unnatural behaviors that would make no sense at all in the absence of the rules. (Location 2498)

Rule beating that distorts nature, the economy, organizations, and the human spirit can be destructive. (Location 2501)

Notice that rule beating produces the appearance of rules being followed. (Location 2513)

Rule beating is usually a response of the lower levels in a hierarchy to overrigid, deleterious, unworkable, or ill-defined rules from above. (Location 2517)

One is to try to stamp out the self-organizing response by strengthening the rules or their enforcement—usually giving rise to still greater system distortion. That’s the way further into the trap. (Location 2519)

is to understand rule beating as useful feedback, (Location 2521)

Designing rules better means foreseeing as far as possible the effects of the rules on the subsystems, including any rule beating they might engage in, and structuring the rules to turn the self-organizing capabilities of the system in a positive direction. (Location 2521)

That’s because the goal is the direction-setter of the system, the definer of discrepancies that require action, the indicator of compliance, failure, or success toward which balancing feedback loops work. (Location 2538)

system, the definer of discrepancies that require action, the indicator of compliance, failure, or success toward which balancing feedback loops work. (Location 2539)

If the desired system state is national security, and that is defined as the amount of money spent on the military, the system will produce military spending. (Location 2543)

It may or may not produce national security. In fact, security may be undermined if the spending drains investment from other parts of the economy, and if the spending goes for exorbitant, unnecessary, or unworkable weapons. (Location 2544)

The GNP is the gross national product, the money value of the final goods and services produced by the economy. (Location 2552)

GNP is a measure of throughput—flows of stuff made and purchased in a year—rather than capital stocks, the houses and cars and computers and stereos that are the source of real wealth and real pleasure. (Location 2566)

rather than capital stocks, the houses and cars and computers and stereos that are the source of real wealth and real pleasure. (Location 2567)

which capital stocks can be and used with the lowest possible throughput, rather than the highest. (Location 2568)

But governments around the world respond to a signal of faltering GNP by taking numerous actions to keep it growing. (Location 2570)

If you define the goal of a society as GNP, that society will do its best to produce GNP. (Location 2573)

nations competed to have the highest per capita stocks of wealth with the lowest throughput, or the lowest infant mortality, or the greatest political freedom, or the cleanest environment, or the smallest gap between the rich and the poor. (Location 2576)

Seeking the wrong goal, satisfying the wrong indicator, is a system characteristic almost opposite from rule beating. (Location 2578)

System behavior is particularly sensitive to the goals of feedback loops. If (Location 2584)

Specify indicators and goals that reflect the real welfare of the system. (Location 2588)

The less of it there is, the better off the city is—even the low-income folks in the city. (Location 2635)

Counterintuitive—that’s Forrester’s word to describe complex systems. Leverage points frequently are not intuitive. Or if they are, we too often use them backward, systematically worsening whatever problems we are trying to solve. (Location 2637)

when I do discover a system’s leverage points, hardly anybody will believe me. Very frustrating—especially for those of us who yearn not just to understand complex systems, but to make the world work better. (Location 2641)

Think about your checking account. You write checks and make deposits. A little interest keeps flowing in (if you have a large enough balance) and bank fees flow out even if you have no money in the account, thereby creating an accumulation of debt. (Location 2649)

hole. The rate at which the hole deepens is called the annual deficit. (Location 2660)

Most systems have evolved or are designed to stay far out of range of critical parameters. Mostly, the numbers are not worth the sweat put into them. (Location 2688)

In fact, there is a large gray area in which both you and the tenant are getting a good, or at least a fair, deal. (Location 2697)

That is to keep oneself unattached in the arena of paradigms, to stay flexible, to realize that no paradigm is “true,” that every one, including the one that sweetly shapes your own worldview, is a tremendously limited understanding of an immense and amazing universe that is far beyond human comprehension. (Location 2984)

All those endeavors require one to stay wide awake, pay close attention, participate flat out, and respond to feedback. (Location 3077)

“What’s wrong?” but also to “How did we get there?” “What other behavior modes are possible?” (Location 3106)

Information is power. Anyone interested in power grasps that idea very quickly. (Location 3148)

we see only what we can talk about. (Location 3157)

A society that talks incessantly about “productivity” but that hardly understands, much less uses, the word “resilience” is going to become productive and not resilient. (Location 3162)

The first step in respecting language is keeping it as concrete, meaningful, and truthful as possible—part of the job of keeping information streams clear. (Location 3177)

Our culture, obsessed with numbers, has given us the idea that what we can measure is more important than what we can’t measure. (Location 3187)

quantity more important than quality. (Location 3188)

Be a quality detector. Be a walking, noisy Geiger counter that registers the presence or absence of quality. (Location 3205)

much cheaper to design policies that change depending on the state of the system. (Location 3223)

Don’t maximize parts of systems or subsystems while ignoring the whole. (Location 3234)

Aim to enhance total systems properties, such as growth, stability, diversity, resilience, and sustainability—whether they are easily measured or not. (Location 3236)

“Intrinsic responsibility” means that the system is designed to send feedback about the consequences of decision making directly and quickly and compellingly to the decision makers. (Location 3254)

Warfare became even more irresponsible when it became possible to push a button and cause tremendous damage at such a distance that the person pushing the button never even sees the damage. (Location 3269)

Garrett Hardin has suggested that people who want to prevent other people from having an abortion are not practicing intrinsic responsibility, unless they are personally willing to bring up the resulting child! (Location 3270)

Working with systems, on the computer, in nature, among people, in organizations, constantly reminds me of how incomplete my mental models are, how complex the world is, and how much I don’t know. (Location 3277)

In a world of complex systems, it is not appropriate to charge forward with rigid, undeviating directives. (Location 3280)

Moreover, when addressing complex social issues, acting as if we knew what we were doing simply decreases our credibility. . (Location 3289)

uniformity and not diversity, and to certainties and not mystery. But there is something else within us that has the opposite set of tendencies, since we ourselves evolved out of and are shaped by and structured as complex feedback systems. (Location 3301)

Another part of us recognizes instinctively that nature designs in fractals, with intriguing detail on every scale from the microscopic to the macroscopic. (Location 3304)

which led to the further ideas of payback periods and discount rates, all of which provide a rational, quantitative excuse for ignoring the long term. (Location 3311)