The ability of a system to cope with shock.

That will do, perhaps, as a short definition. But this is a case where we need to know more, so here is a more considered way of looking at it. Resilience is . . .

The capacity of a system to absorb disturbance and reorganise while undergoing change so as to still retain essentially the same function, structure, identity and feedbacks.R45

There is nothing wrong with that except that it can still leave you wondering what resilience is really about, so here is another way of coming at it. Think of a shallow lake whose water is kept clear by the vegetation growing in it, which releases oxygen and maintains a healthy population of small water bugs which feed on nutrients in the water. Perhaps there are also some fish which feed on the bugs. This, we may assume, is a stable condition; sunlight gets into the water for the plants, and even though there are times when it gets an excess supply of nutrients from, say, falling leaves in the autumn, or from a local farm, it is able to cope with this by cleaning up the nutrients, and it remains clear.R46

However, one day, it receives so many nutrients from various sources that it reaches a ‘tipping point’ at which, quite suddenly, it flips into a new state: turbid water, rich with algae which block out the light, killing the plants, and so reducing the oxygen level to the point at which much of the other aquatic life dies. Now it will remain in this new stable condition. Indeed, it will hold onto this condition even if the extra supply of nutrients then declines to a level which would have presented no problem for the pond in its former condition of plants and clear water. That is to say, there is a wide band of intermediate levels of nutrients at which the lake will remain turbid if it is already turbid, or clear, if is already clear.

So, what we have here is two states of resilience, both of which hang on to their current state with tenacity until they can do so no longer. But when the level of nutrients strays towards extremes, the whole pond ecology suddenly flips into a new state. The image often used to illustrate this consists of two adjacent basins, known as “valleys”, or “basins of attraction”. The system (like a ball kept in the basin by its high sides) is either in one condition or in the other, and “resilience” means that it tends to stay in the one that it is already in, unless an exceptional disturbance comes along which jolts it into the adjacent one.R47

C.S. Holling is the ecologist whose work on resilience in this sense is most widely recognised, and he defines resilience in this context as . . .

. . . the size of the valley or basin of attraction around a state that corresponds to the maximum perturbation that can be taken without causing a shift to an alternative stable state.R48

Lean Logic’s definition is this:

Resilience is a system’s tendency to stay in the condition it is already in, despite shocks.

In fact, we could cautiously modify this by changing just one word: “Resilience is a system’s ability to stay in the condition it is already in, despite shocks.” That revision suggest that the system takes active steps to stay in the condition it is already in: it specifically compensates for, corrects and cures shocks, just as the white blood corpuscles in our bodies attack and destroy infections. The only problem with that one-word revision is that it suggests that nature is purposive—and the purposive, or teleological, view of nature implies the existence of a mind and of intention which we cannot really claim in the case of a pond, or an ecology, or a planet. This is the idea that has brought so much trouble to James Lovelock in his theory of Gaia. So let us stay out of trouble and settle for “tendency” for now.

We can think of our definition as the Resilience Rule. Ecological systems do not always succeed in staying in the condition they are already in: large events may overwhelm them, or small events (the butterfly effect) can start a sequence of events that overwhelms them. But the forces of continuity and stability (homeostasis) are powerful—as demonstrated by the stable temperature and metabolism of our bodies. This holds true on scales ranging from small—e.g., a shallow lake—to large—e.g., Gaia—though it does not change the fact that ecologies’ maintenance of conditions which favour their own continuation tend, ultimately, to fail (although . . . see Wheel of Life).


That is resilience from the ecologist’s point of view, but Lean Logic’s interpretation extends to community. In the future, people may want to make conscious decisions about how to cope with disturbance. And unlike a shallow lake, they may give some thought to the matter. For instance, they may wonder whether there could be more than one kind of resilience, and whether there may be a choice between them—and conscious strategies for getting to the preferred kind.

In order to think about this, a good place to start is with those basins, which are redrawn here. Let us suppose that the left-hand basin is the preferred state (an orderly, life-supporting community). The right-hand basin is undesired—some combination of chaos, crisis and failure which the community wants to avoid. Fortunately, there is a barrier between the two basins, so that the community can say that it is resilient in the sense of being reasonably confident of remaining in the left-hand basin, unless a shock comes along which is exceptional. On the other hand, that high barrier could turn out to be a problem because, if a shock does take you over the barrier into the right-hand basin, it could be hard to get out (like the turbid lake which remains turbid, even though conditions have improved). The new state will have a resilience of its own: undesired states can be resilient, too. You will be stuck in a place you don’t want to be in. It might not be a place which can support the life of the community.R49

However, the community is also aware that exceptional shocks do happen. Quite often, in fact. So it decides to think about a strategy. The image of the basins suggests that there are two possible strategies. One is to raise the height of the barrier between them. This will reduce the probability that, when the shock comes, they will tip over into the right hand basin. The other strategy is to lower the height of the barrier between them. This will increase the probability that a shock might tip them over into the right hand basin, but it will mean that—if/when that happens—there is a much better chance of being able to get back. This suggests that there is a case for exploring two kinds of resilience:

1. preventive resilience; and

2. recovery-elastic resilience.


A visit to Tuscany

Think of two populations, each based in eight villages, living in practically identical locations, long ago—each in fertile Tuscan valleys beside small rivers.

Now imagine that, 200 years ago, their previously-similar histories diverged. One of them (call it L’Aquila) decided to join together as a town, surrounded by its fields. They argued that if they joined together, they could achieve things which were not practical as separate small villages. This intensification would enable them to build larger buildings, including a larger church, maintain a library, attract visiting scholars, defend themselves better against troublesome neighbours, and even cause a spot of trouble themselves if they felt like it. The other population (call them the Passero villages) just carried on as they were, in loose contact with each other, falling out sometimes, but mostly getting along and learning from each other.

Then there are two disastrous events.

First a flood. One day, there is a massive rainstorm. The rivers rise rapidly. The valleys reveal their true nature as floodplains. The consequences for L’Aquila and the Passero villages are very different. Both L’Aquila and the villages had been aware of the danger of flooding and had followed the policy of enlightened inaction needed to keep it to a minimum. They had conserved the watershed, especially the forests that covered it. They left untouched the marshland that flourished in the higher reaches of the river, along with the meanderings that lengthened it and evened out the flow, enabling it to hold more water than it could have held if it had been straightened.

But then L’Aquila went further than that. They wanted water to irrigate their crops during dry summers, as well as reducing to the minimum the risk of flooding in the winter. To that end, they built a series of sacrificial lakes along the course of the river towards the valley. They allowed the lakes to fill up in the spring, and gradually emptied them (hence “sacrificial”) in the summer, letting their water flow into the river for irrigation. They were then kept empty through the winter, except when a flood threatened, when they were allowed to fill up, holding back some of the excess water from the river, and preventing floods. During the summer, the flow of water from the lakes was used to provide power for a watermill, which ground all the flour needed by the town. Building the dams, the sluices, the canals and the mill for all this required a lot of labour. In fact, it required a whole class of manual workers, working intensely during the winter when there was less agricultural work to do. It required a rather authoritarian profession of overseers and planners, and it needed to be managed by a class of priests, who lived in water temples and (since their role placed them in a strong position) demanded tribute and exercised power over everyone living downstream. But the arrangement made L’Aquila rich, and it was able to build fine roads for the transport of food to its growing population.

Now comes the rain. It is awesome, and yet a devastating flood is prevented. At the same time, L’Aquila has a reliable flour mill and in the summer it is protected from drought.

For the Passeri, such lakes were beyond their capability. The villages were well able to get together to deal with immediate problems, but they could not contemplate a large, long-term programme like that. Their peasant farmers would not agree to leave home for weeks on end in the winter to build dams and dig canals. They did not have the central organisation, nor the money to maintain a class of priests living in water temples. Instead, they adapted their farming to droughts, and made do with intermittent and rather inefficient watermills which only worked in the winter (the one village on higher ground had an inefficient windmill). This was a largely egalitarian society, not without its leaders and teachers, but seeing itself as a community of individuals rather than as hired or coerced labour. In any case, the villages did not always get on very well. One of them, in particular, was a troublemaker, and was suspected of a little bit of sheep-stealing (for immediate consumption) from its neighbours. It had not reached the level of a feud—priests from the other villages would go and tell them off, and there was intermarriage between all the villages—but they did not do large-scale cooperation. And another of the villages was quite beyond the pale, as we shall see. So serious coordinated action between all eight was out of the question.R50

As such, when the rain comes to Passero, the valley is flooded, and the eight villages all respond in different ways. Here is what happens to them:

1. One of them loses almost half its livestock and some of its members; most of its stores of grain in the barns are swept away before the survivors manage to reach higher ground. And yet, they are philosophical about it. Some of the young leave home, but some come back with wives and husbands. Neighbours help them out with grain and livestock. Five years later, their barns are repaired, and they have as many people and livestock as before.

2. The second village also loses many sheep and some of its people, and their homes are wrecked. They are so devastated and demoralised by these losses that they lose confidence in their skill as farmers. They hold a council and decide to go into business making boats. They have learned the craft to some extent, building a few rudimentary fishing boats for their neighbours, but the flood has concentrated their minds. Some may go back to farming in the valley one day if the family expands, but for now they go into a new phase in the boat-building business.

3. The third village has a much more flexible response to the flood. They do not keep any livestock, so they have none to lose, and nobody has to risk their lives trying to rescue them. They have gardens, but they get their protein—and earn a living—from fishing. They lose most of their goods, and their houses are largely destroyed, leaving just the timber frames intact, but their fishing boats survive, tied securely to trees. The flood is flowing too fast to allow them to do anything with them, so they sit tight until the flood subsides. Then they begin the task of repairing the damage.

4. The fourth village is known locally for being the tough guys of the valley. They are wrestling champions of their region. No one for miles around would dare to steal any of their sheep, or try anything on with any of their women. They work on the principle of being prepared for anything: they do daily workouts and archery practice; their houses and their barns are built for endurance, on two floors. They have no use for carpets or soft furnishings. Even their sheepdogs are tough, trained to round up their flock in a moment and to drive them up into the barns. The flood when it hits them is just as deep as elsewhere, but they are not much affected by it. The flock is taken to safety in a well-rehearsed routine. Like the giant stones with which they built the foundations of their houses, and the solid wood frames which they placed on top of them, they are essentially undamaged and need time only to dry off. Repairs go ahead at speed and without complaint. No tears are shed. They have Widerstandsfähigkeit, resistance-capability.

5. The fifth village is the one with the bad reputation for causing trouble by stealing sheep. They are also caught by the flood, but they do not have far to go to reach higher ground. In fact, they get out so fast that they have time, before the worst of the flood, to go back with their horses to rescue as many of their neighbours in the second village as they can. And they make it clear that they expect to get some land from them as a thank you when the second village announces that it is going into the boat-building business. After the flood they are rather better off than they were before it.

6. For the sixth village, the experience is quite different. In fact, it cannot really be called a village at all, for this group has still not moved on from its preference for the life of the hunter-gatherer. They have no livestock, gardens or settled territory. This offends the sensibilities of the agriculturalist villages, who often feel they ought to be exterminated, but they are related by marriage, and they sometimes do the villages a favour by culling the wolves that dine off their sheep. This traditional society has the advantage of simplicity, or elegance, in the language of Lean Logic. They live in tents made from skins. They have no infrastructures—no sheep, no houses, no gardens, no fishing boats. All their needs are wants.

When the flood comes, they do not even need to saddle their horses—they ride bareback, and with the first sign of danger they pack up and vanish. A couple of hours later they are on one of their favourite upland camping grounds ten miles away, with the horses grazing as if nothing had happened.

7. The seventh village is completely swept away.

8. The eighth village is lucky. It lives a little bit up the hillside, where the land is less good, and is hard to cultivate because of the slope, but it keeps them out of danger when the water rises. They watch in horror as the other villages try, with mixed success, to save themselves. But it is a good thing that they survived, because they hold the original manuscript of the mass written for St. Maximus of Aveia, which is brought out and performed by all the villages in a ritual show of solidarity and reconciliation on the Saint’s Day (10 June).

Then the earthquake. Just twenty years after the flood, there is an earthquake. L’Aquila is by now a rich town, able to obtain the materials and labour it needs from the whole region. Over the years, it has used expensive limestone blocks to build impressive streets and a basilica with a dome. The Passero villages could only afford materials that were close at hand, especially wood, making for rather unimpressive timber-framed buildings rising to no more than two floors, with the spaces between the timber filled with various materials, including mud, reinforced as wattle-and-daub.

When the earthquake comes, the buildings of L’Aquila are devastated, and the loss of life is great. Much of the population has to evacuate, finding temporary accommodation all over Italy. The dams fail; the watermill is destroyed. The recovery of L’Aquila’s economy and culture is in the balance, and people compare the disaster with the Lisbon earthquake of 1755.

For the Passeri, the effects are quite different. Their houses sway gently, and some of the mud fillings collapse, but they stay upright. People whose houses are most seriously damaged lodge with neighbours for the few weeks needed for repairs. Their watermills are damaged, but they have only ever worked for half the year, so many of the houses have handmills as a backup. Their economic life is almost unaffected, apart from the time needed for repairs, and the local farmers and other craftsmen, who are used to working with their hands and enjoy the luxury of a slack economy with a short working week, patch up the houses. Soon, things are back to normal (for the sixth village, the earthquake is not a significant event at all: when the earth sways, they are amused by it).

So, let us now look at the forms of resilience displayed by L’Aquila and the Passeri.


Strategies of resilience

Here we have strategies of two fundamentally different kinds. L’Aquila’s strategy is preventive resilience; the Passero villages’ strategy is recovery-elastic resilience.

The common usage of “resilience” contains the sense of surviving adversity which would have destroyed a less resilient community or person. In Lean Logic, the meaning of resilience includes all that, but it also extends closer to the source of the problem; applying highly-developed skills to prevent the shock happening in the first place.



Preventive resilience—like L’Aquila’s sacrificial lakes—protects a system from being substantially damaged by a hostile environment. The system has the capability of changing its environment to suit its nature, or changing its nature to suit its environment, or both. The key to preventive resilience lies in the possession of a structure consisting of many differentiated parts and functions which join up: there is connectedness—strong interdependence—forming a system, an organism, or a community with the defining characteristic of complexity.

But it has a downside. The complex system’s specialised parts—and the long chains of interdependence between them—make it fragile. Damage to one part can disable the whole system. When a shock is not prevented, the consequences are likely to be devastating.



Recovery-elastic resilience, by contrast, does not avoid shock: it responds to it. So far as it can, it goes with the flow; it uses its ingenuity and invents workarounds; it is elastic, flexible. Afterwards, it engages in repair and recovery; it has endurance. Corresponding to the stories of how the different Passero villages coped—or failed to cope—with the flood, the forms of recovery-elastic resilience they displayed are, respectively:

1. Sacrifice-and-succession. Although parts of the system endure, other parts are destroyed. The system allows for this by producing more than it needs to replace itself (as we see in the high fertility of virtually all plants and animals in a natural ecosystem). It invests a large proportion of its assets in conserving the genetic code for the next generation and in educating the new generation in the culture needed to keep the system alive. The sacrifice of parts gives the system as a whole immortality.

In a sense, sacrifice-and-succession can be seen as a continuous process of repair. The repair doesn’t always provide an exact replacement, but it fills the gap, either with more of the same, or with another part of the ecology.

2. New phase. The system responds to the shock by shifting into a new phase, taking on a different character while the changed conditions last. One example of this is the forest which burns and then reverts to a grassland for a time, before becoming forest again. Ecologies and societies are transformed by climate changes; the new state will last as long as the conditions which favour them.R51

An even more radical adaptation happens when part of the system changes permanently—or at least for the very long term. Hunting the giant herbivores of North America to extinction, urbanisation, genetic change, climate change, desertification, the exhaustion of mineral and fossil fuel resources—these are all permanent changes, or associated with permanent change. If a living system changes out of recognition owing to a shock, but at least continues as a living system, that can be taken to be a form of resilience—but of course it is a reminder that we need to be specific about which “system” we are referring to. If it is, for instance, the giant herbivores of North America, they indeed proved not to be resilient to the climatic changes and other shocks following the end of the last ice age. But the ecosystem they belonged to did: it adapted; life went on.R52

3. Elasticity. This is flexibility in action. The system invents coping strategies; it bends with the storm; it behaves in a way which is not normal for it, survives the shock, then comes back to recover its former way of life as far as it can.

4. Resistance (but perhaps Widerstandsfähigkeit—resistance-capability—gets closer to the meaning). Here we have the hardness and imperviousness of a rock. It can endure large shocks without damage. It is the opposite of a house of cards: it hangs together. A person with this quality has a sense of humour, being able to laugh off insults; a community with it can cope with trouble without breaking down; it is thick-skinned, bombproof. It is not so much a case of recovering from shock, or being elastic in response to it, as being hard enough to be unaffected by it. If this is in place, then the shock would have to be on a very large scale indeed for the system to notice it.

5. Opportunism. Parts of the system use the damage as an opportunity. They fill the gaps. They use the reduction in—or absence of—competitors as a chance to flourish in ways which would have been impossible for them if the competitors were there. Plants that live in environments that no other plants could tolerate (such as lyme grass, discussed in Diversity) demonstrate this form of recovery-elastic resilience.

6. Elegance. The system has minimal infrastructure. It does not depend on long supply lines for food and materials. It is not affected by damage to essential assets over which it has no control. It has little or no intermediate economy, little or no stuff. All the Passero villages have elegance—this is one of the direct consequences of their small scale—but the sixth ‘village’ has taken elegance to the limit. Or, rather, its inhabitants have kept their elegance intact, being hunter-gatherers and resisting the temptation to settle down and go into agriculture—which, from what they have seen of it, looks like hard work (Ecology: Farmers and Hunters).

And the strategies of the seventh and eighth villages? The seventh village was swept away entirely, so it does not at first glance seem to provide an example of resilience. But in the context of all the other villages, this is a case of sacrifice-and-succession on the scale of a whole village, rather than only within one. It may allow the wider society to learn lessons. And the eighth village, which escaped the flood, reveals resistance in the collective sense, too, since recovery depends on the shock being survived by all the information it needs—by the culture and/or the DNA which it cannot rebuild. The eighth village was the system’s continuity in this sense, for it was keeper of the Mass of St. Maximus. The Passeri could face the future with their key cultural icon intact.

All of these strategies of recovery-elastic resilience are possible where a system is subdivided into relatively small, weakly interconnected units, like the Passero villages. The system is modular.


Resilient systems

Since resilience is of two kinds—preventive and recovery-elastic—the properties of the systems capable of each are sharply different. Preventive resilience is the form of resilience mainly open to a complex system; recovery-elastic resilience is the form of resilience mainly open to a modular system.

Now, an important aside: the type of complexity that L’Aquila developed is in fact a special case. It is not the fully developed complexity of an organism, although it does achieve some of the qualities of such. No, what we have here is ‘as-if complexity’—which this Dictionary calls complication. In this present entry we consider cases of both true complexity and ‘as-if complexity’ interchangeably, because the implications of the two types of complexity are similar—and highly relevant to our own future. Exactly what complication means and how it comes about is explained in the dedicated entry on Complexity. But for now just bear in mind: complexity as applied to a developed human society is ‘as-if complexity’.

And with that said, back to the lessons of Tuscany, where we shall use “complexity” freely, knowing that we get to grips with the small print elsewhere.

So, resilience is of two kinds, and it is possible to see a pattern here, as each kind has its cluster of complementary properties. As summarised in the table, “The Properties of Resilient Systems”, we can think of resilient systems as ranging between the complex and the modular, with corresponding expressions of diversity and connectedness:



Preventive Recovery-elastic
System type Complex Modular
Diversity Strong
Connectedness Strong


The characteristics of a system with regard to these three criteria define the nature and extent of the resilience it can achieve.



Resilient systems, then, lie along the spectrum between complexity and modularity. In fact, they may occupy a range along the spectrum rather than a point, because many ecological systems have attributes of both complexity and modularity. But let’s first consider systems which have stabilised close to one extreme or the other—complex or modular: the antelope is complex; the herd of antelopes is modular (even though it is made up of complex antelopes).

1. Complex

A system which is capable of preventive resilience is a complex system. Complexity can be interpreted in several different ways, but for Lean Logic it is the property of a system—such as an animal’s body or a self-reliant community—whose parts have strong differences in function, carrying out different, complementary roles in the interests of the system as a whole. These interdependent parts and their functions are connected by extended links—such as the veins and nerves in the human body—and there is little redundancy or duplication.

In the case of an animal’s body, the different functions are performed by organs with specialised structures. In the case of a human society, these different functions can take the form of specialised professions, duties and abilities; and as we saw in the way L’Aquila set about the diverse and demanding tasks it set itself, one of the expressions of this differentiation will be varying degrees of inequality.

Either way, such differentiation of roles gives a system capability. A complex system with well-evolved specialisms can develop strategies of commanding brilliance, rising above the grim survival strategies which we associate with “resilience”. Like L’Aquila, it may be able to foresee a threat and prevent it. It may use a range of connected and coordinated tasks to achieve high levels of ambition and beauty, such as the cathedrals and orchestras of a complex human society, or the athletic virtuosity of the falcon.R53

However, the complex system has poor recovery-elastic resilience. It does not adapt easily in response to profound and sudden shock: all those connections inside a complex system make it quite inflexible and vulnerable to trauma. It cannot use the sacrifice-and-succession strategy, for instance: if wounded, it is likely to die. A complex system would have been capable of some of the individual Passero responses—adaptation to a new phase and opportunism, for instance—but the mutually-dependent, tightly-connected functions of its parts would have made it hard, or impossible, to respond in more than one of those ways at the same time.

Complex systems do not travel light. They can at times be inventive, but their complexity is likely to take the form of specialisation—e.g., swift running like an antelope; being capable of thriving in heat and drought like a cactus; or living in the deepest ocean depths like the eelpout. By these standards, humans have exceptional versatility—but outside their capabilities, complex systems find themselves in trouble. And they only have one shot at it, whereas modular systems can fail again and again and still survive. For a complex system, just one bullet, one fall from a horse, one snakebite, is likely to be the end of the matter. Complex systems need their ability to prevent shock, for their recovery-elastic resilience to a shock that they don’t prevent is poor. The cost of their brilliance is their fragility.R54

If the hero escapes to fight another day, that tells us something about his preventive resilience. With stop-at-nothing enemies like the ones he has made, recovery-elastic resilience wouldn’t have been much help.

2. Modular

Modularity is the property of being subdivided into parts (or subassemblies, holons, modules . . .) which have a degree of independence. Every module carries out the essential functions required for its own self-reliance. There may be links of beneficial reciprocity between parts, but they are not indispensable; if some modules are damaged or die, the effect does not ripple through to the rest—every antelope or Passero village is capable of feeding itself if needs be. The modules are elegant in that they avoid long and vulnerable lines of supply, and this sets a limit on their size: all the six strategies of recovery-elastic resilience depend on the systems in question having the flexibility of small scale. The other two key enabling properties of modular systems are weak diversity and weak connectedness, and we shall come to these in more detail in a moment.

Now for the key link between complexity and modularity. A modular system requires that each module within it must have a high degree of local competence and independence—and, in order to achieve that, the modules themselves must have complexity. If the modules are communities, they must be capable of aspects of self-reliance such as capturing and delivering the energy they need, producing food, dealing with waste, maintaining homeostasis—and that means that they will have internal structures that are far from modular. A modular (and therefore recovery-elastic) system consists of modules which are not recovery-elastic. So both kinds of resilience, both preventive and recovery-elastic resilience, can coexist within the same structure—but they inhabit different layers. Higher levels of complexity are characteristic of lower layers in the system: the complexity of the parts supports the modularity of the whole. There are qualifications to all this, but, as a general rule, preventive resilience is the individual accomplishment of a complex system; recovery-elastic resilience is the collective accomplishment of a modular system.

And a loose, modular structure has other positive features, too, beyond the defensive capabilities of resilience. It provides space and freedom for its parts to develop and apply their complex intelligence. It permits diverse solutions, trial and error, evolution and local flexibility. It confers responsibility on its members to take the initiative. It affirms, protects and depends on presence. The complex parts of such a system are weakly linked (loosely coupled) within its modular whole. Its resilience consists of both the local brilliance of its parts in keeping out of trouble and the collective ability of the whole in recovering when that fails.

These are critical, life-saving benefits. By contrast, modular communities that seek to build their intelligence and competence by joining up into an integrated system of tightly-coupled complexity (complication) may have some success for a time, but the loss of modularity that this involves will in due course destroy them.

But note the fuzzy borderlines and anomalies here, which ensure that any statement has to come with disclaimers and exceptions. There are modular properties in complex systems (cells are constantly replacing themselves in the body; the body’s powers of recovery from non-lethal shock are considerable), and complex properties in modular systems (specialisms and exchanges of scarce materials between communities). And the crucial asset of community itself sits between the two properties. So precision is off the menu. But the complementary relationship between modularity and complexity holds. Ask an antelope. The herd may lose one or many of its members and still be a herd. For a single antelope, one incision somewhere in the region of the throat is the end of it. That’s complexity for you.



Diversity—the variety of forms, structures or species in a system—is a defining condition of resilience. And here, too, we find a spectrum, between:

1. Strong (structural) diversity

In a complex system, the differences between parts—between the organs, the arteries and nerves of the body, for instance—are radical. There is little or no duplication of form, reflecting their very different tasks. And there is strong interdependence (connectedness), with each part owing its existence to successful coordination with the others. An animal is a network of transport links: if any of them get blocked, it will probably die. Individual freedom for the diverse parts in a complex system is minimal.

2. Weak (textural) diversity

This is the diversity that exists between the parts of a modular system—the antelopes in a herd, the communities in a network like Passero, the varieties in a species. The diversity is intrinsically restrained: it is like variations on a musical theme. There is a lot of duplication of parts.

None of the six strategies of recovery-elastic resilience make sense unless the parts of the modular system are similar to one another. For instance, sacrifice-and-succession (as with the people and livestock in the first village, and the seventh village itself), only works if the parts are sufficiently like each other for the idea of replacement, or succession, to have some meaning. Adaptation to change in the form of parts collectively going into a new phase only makes sense if there is essential similarity between the parts in the first place. The opportunist strategy—rescuing neighbours in trouble and then claiming a reward—is not the action of an enemy or a predator, but part of politics: unscrupulous behaviour being transcended (just) by shared interests.

That herd of antelopes is being cited in this discussion so often that they are in danger of becoming domestic pets. Nevertheless, they cannot be bettered as an example; here is a modular population of very similar parts, so recovery-resilient that it can survive for thousands of years in an environment full of animals that want to eat them, and consisting of individuals that have a high degree of uniformity—or, as Elinor Ostrom calls it, homogeneity (Commons). Indeed, if one part of a modular system is substantially different from the others, that is likely to bring trouble. The albino antelope has a short expectation of life.R55

And such essential uniformity has practical benefits beyond its significance as a condition of recovery-elastic resilience. Basic similarity between the parts of a modular system provides a framework for their cooperation, reciprocity, conversation and trust within an agreed culture and shared language; the ample presence of your own species means a range of choice for breeding and the spreading of genes beyond the local population; it invites coming-together for carnival, wide shared responsibility for the environment, rapid learning from each other’s invention and experience and, if necessary, cooperation for defence.

But there are, of course, limits to the benefits of homogeneity. In a modular system of communities like Passero there is diversity in the form of local variations, and local ecosystems too are adapted to the particular place and circumstance; the specific local character, particularity and enchantment is intact. Although some responses to local conditions won’t work, others have at least a good chance of doing so, and the successful can then be imitated and reproduced, so evolution and emergence are in place.

Such (weak) diversity is especially important if an ecosystem is under stress, and a classic study demonstrating this was published by David Tilman and John Downing in 1994. They cultivated hundreds of grassland plots on the flatlands of Minnesota, with varying degrees of diversity. The plots that performed best—notably in their ability to survive drought—were those with the most (bio)diversity.R56 Tilman puts such diversity into its context as only one of the conditions determining the resilience of an ecosystem, but emphasises that it is a necessary one. He summarises,

Diversity must be added to composition, disturbance, nutrient supply dynamics, and climate as a determinant of ecosystem structure and dynamics.R57

The weak diversity within a modular system such as a grassland is still nowhere near the structural diversity inside a complex system—but some systems, such as a woodland ecosystem or an established community, provide some sense of a middle ground. The woodland has modularity, with its recovery-elastic resilience; it also has a degree of complexity, with diverse roles and some interdependences. It has both preventive resilience and recovery-elastic resilience—up to a point. In a turbulent environment where there are no certainties this limited each-way bet provides the most secure protection of all.R58



Now we come to the third pairing: slack and taut.

So far, we have established that a modular system actually depends on having complex parts. So the independence (weak connectedness) within a modular system and the interdependence (strong connectedness) within a complex system depend on each other. The parts within a complex system are so strongly connected that they have almost no freedom—your heart and liver must carry out instructions coming from some combination of brain, nervous system and local chemistry. But this internal interdependence confers a high degree of freedom and capability on the complex system (in this case, you) acting as a whole.

It can apply this freedom of action within the space allowed by the modular system to which it belongs (in this case, your community). In other words, a complex system like you can only make use of its powers of intelligence and foresight—its ingenious response and avoidance—if it is part of a modular system which gives it the freedom to do so.

So just as complexity and modularity are mutually dependent, so are strong connectedness (taut) and weak connectedness (slack). The taut brilliance of a complex system is only revealed and able to express itself because it lives in the context of a slack system. The complex system makes choices; the slack system enables choices to be made. And this allows the slack, modular system as a whole to benefit from the preventive resilience of its parts.

1. Taut (strong connectedness)

A taut, complex system makes few concessions to the freedom of its parts. The strength and astonishing capability of a complex system such as a peregrine falcon does not lie in its spare capacity and its ability to recover from trauma, but in its efficiency and in the exact, lean skill with which it earns a living. It has the practised specialism of the hunter. Its assets consist of intense, taut athleticism, observation and precision, kept sharp by daily contest with animals who would prefer peregrines to starve. It is anything but slack:

Its shape is streamlined. The rounded head and wide chest taper smoothly back to the narrow wedge-shaped detail. The wings are long and pointed; the primaries long and slender for speed, the secondaries long and broad to give strength for the lifting and carrying of heavy prey. The hooked bill can pull flesh from bones. It has a tooth on the upper mandible, which fits into a notch in the lower one. This tooth can be inserted between the neck vertebrae of a bird so that, by pressuring and twisting, the peregrine is able to snap the spinal cord. The legs are thick and muscular, the toes long and powerful. The toes have bumpy pads on their undersides that help in the gripping of prey. The bird-killing hind toe is the longest of the four, and it can be used separately for striking prey to the ground. The huge pectoral muscles give power and endurance in flight. The dark feathering around the eyes absorbs light and reduces glare. The contrasting facial pattern of brown and white may also have the effect of startling prey into sudden flight. To some extent it also camouflages the large, light-reflecting eyes.

. . . The eyes of a peregrine weigh approximately one ounce each; they are larger and heavier than human eyes. If our eyes were in the same proportion to our bodies as the peregrine’s are to his, a twelve stone man would have eyes three inches across, weighing four pounds. The whole retina of a hawk’s eye records a resolution of distant objects that is twice as acute as that of the human retina. Where the lateral and binocular visions focus, there are deep-pitted foveal areas; their numerous cells record a resolution eight times as great as ours. This means that a hawk, endlessly scanning the landscape with small abrupt turns of the head, will pick up any point of movement; by focusing upon it he can immediately make it flare up into larger, clearer, view.R59

That is a taut system.

2. Slack (weak connectedness)

The slack comes at the level of the modular ecology of all peregrines in an area. They hatch many times more chicks than they would need to replace the population if they all survived. There is redundancy in the population of hawks; and also in the ecology of their habitat, whose existence depends on the succession of death and life of its members. The natural, ecological system is designed to take losses. It can change—profoundly and quickly—in response to change in the climate and setting. Internal to the hawk and its ecology alike, there are complex, taut structures with little or no freedom to change their highly-evolved forms in the light of present circumstances, but the modular ecologies that they live in have redundancy and room to adapt. They have slack; they therefore have recovery-elastic resilience.

The difference between taut and slack, then, is vital. Here is an illustration. It is about a disturbance occurring on two occasions—past and future—widely separated in time. The first time, the intensity of the disturbance was extreme and sudden, but the consequences for the slack systems of the time were moderate. The second time, the disturbance could be comparatively moderate, but the consequences will not, for the systems it affects have become taut and complex, and so much less able to cope with a shock they cannot prevent:

The next century of human-made global warming is predicted to be far less extreme than that which occurred at 9600 BC. At the end of the Younger Dryas, mean global temperature had risen by 7°C in fifty years, whereas the predicted rise for the next hundred years is less than 3°C; the end of the last ice age led to a 120-metre increase in sea level, whereas that predicted for the next fifty years is a paltry 32 centimetres at most, rising to 88 centimetres by AD 2100. However, while future global warming may be less extreme than that of 9600 BC, the modern world is in a far more fragile state. . . . As a consequence, the threats to human communities and natural ecosystems are far more severe than those of prehistoric times.R60

In a sense, a complex system is permanently on the threshold of collapse. It uses its taut complexity, and the capability it provides, to keep its nemesis at bay. When it can no longer do so, it reaches the tipping point which will take it back to a much less complex order. A slack, modular system lives much less close to the edge.



Underlying all these properties of resilient systems is, of course, the matter of feedback: “A resilient world”, write Brian Walker and David Salt, “would possess tight feedbacks (but not too tight).”R61

Systems—individuals and groups—need to be aware of what is going on around them, but rapid awareness does not necessarily mean rapid response. The ideal timing is not always immediate; even procrastination can have its value if what you haven’t yet got around to doing is nuts.

And yet, there is a danger of begging some questions here. For we have got this far, almost to the end of this brain-busting entry on resilience, without being sure of how to tell which system we are talking about. Consider the case of the village that made its living in part by raiding its neighbours for their sheep, for example: was the resilience that mattered to them their own resilience as a village or the resilience of all the Passero villages? We are all, in a sense, parasites to our hosts and hosts to our parasites.

This is a moment to let a picture tell the story. Here we have our familiar pair of basins from the start of this entry, but now with another pair of basins inside one of them. And of course we could extend that with a series of further basins without evident limit—both smaller ones inside the small pair and larger ones containing the large pair. There is likely to be interdependence between them: the small pair’s resilience depends on the resilience of the basin in which it lives. And yet, there is also a need for judgment—for a choice of priorities, and for reflection on who you are—for defining the identity which is a necessary condition for rational decision.R62

If we were antelopes, we would not need to worry about such matters. If we made a wrong decision about who we were, and which basin it was that we wanted to stay in, then the mistake would quickly be corrected for us; we wouldn’t survive to make it again. Humans, by contrast, with their powers of preventive resilience, can hold off such tight feedback loops. If only resilience were a formulaic guideline for how to cope in an intensely difficult time, that would make things so much easier. Thinking about it takes us into an exploration of complexity and modularity, the deep nature of systems and the strategies of life and death in a turbulent environment. And it sets things up for the story of the Wheel of Life, which sees complex systems like our own civilisation through their whole life-cycle.

Resilience does provide some guidelines. It can be an inspiring idea, and in critical ways it sets the agenda for transition. But it does not do our thinking for us; it just tells us where to start.R63


Related entries:

Reflection, Gaia, Butterfly Effect, Climacteric.

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David Fleming
Dr David Fleming (2 January 1940 – 29 November 2010) was an economist, historian and writer, based in London. He was among the first to reveal the possibility of peak oil's approach and invented the influential TEQs scheme, designed to address this and climate change. He was also a significant figure in the development of the UK Green Party, the Transition Towns movement and the New Economics Foundation, as well as a Chairman of the Soil Association. His wide-ranging independent analysis culminated in two critically acclaimed books, Lean Logic and Surviving the Future. A film about his perspective and legacy - The Sequel: What Will Follow Our Troubled Civilisation? - was released in 2019, directed by BAFTA-winning director Peter Armstrong. For more information, including on Lean Logic, click the little globe below!

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