Strange parallels

Victor Lieberman uses the phrase, "strange parallels," as the title for his two-volume study of Southeast Asian history (Strange Parallels: Volume 1, Integration on the Mainland: Southeast Asia in Global Context, c. 800-1830). Besides offering a highly expert history of Burma and its many kingdoms between 800 and 1830, Lieberman poses a fascinating and novel question: how can we explain the substantial historical parallels that existed between Burma and various parts of Europe, including especially France and Russia? He writes:

In fact, in mainland Southeast Asia as well as in France, the late 18th and early 19th centuries ended the third and inaugurated the last of four roughly synchronized cycles of political consolidation that together spanned the better part of a millenium. (2)

fig. 1.2. Territorial consolidation (p. 4)

The figure illustrates the kind of synchrony that Lieberman is highlighting -- over a sweep of some thousand years, there is a rough-and-ready correspondence in the patterns of territorial consolidation that existed in Burma and France.

Lieberman poses the crucial historical question in these terms: "Why should distant regions, with no obvious religious or material links, have experienced more or less coordinated cycles? If we discount coincidence, what hitherto invisible ties could have spanned the continents?" (2)

Apriori there appear to be only a small number of logically distinct possibilities that could explain the fact that patterns of variation are synchronized between A and B. (1) It may be that there is a causal linkage from A to B such that A's variations stimulate subsequent variations in B. (2) It may be that there is a common cause C whose variation simultaneously causes variation in both A and B. Global climate variation might be such an example. (3) It may be that both A and B are running through their variations according to the same internal clock, with the result that their variations are synchronized without causal interaction -- like two clocks ringing out the hours in tandem or two adolescent children going through roughly the same developmental stages at roughly the same time. (4) It may be that the observed synchrony is simple coincidence, with no causal explanation whatsoever.

So far as I can see, this exhausts the logical possibilities; there is no fifth possibility.

To further complicate the picture, Lieberman points out that there were other regions of the world where these patterns of consolidation did not occur, or did so on a very different timeline. So we can exclude the idea that there was some common global cause leading to simultaneous pulses of consolidation; rather, Southeast Asia and Western Europe were synchronized, but India was not.

Lieberman's explanation of this observed historical synchrony goes along these lines. He believes that both internalist and externalist approaches have a role to play. The internal historical dynamics of the state systems in Burma and Western Europe were governed by particular local factors. But they each created a tendency towards consolidation of land and power. And external factors provided periodic "pulses" that served to synchronize these internal patterns of development. So the effects of an external factor -- maritime trade -- pushed both Western Europe and Burma into extended periods of state formation and consolidation. This story combines (3) and (2) above: local processes that are developing according to their own imperatives, and occasional system-wide pulses that bring these local processes into synchrony. And the explanation allows Lieberman to place the intellectual frameworks of both Tilly and Wallerstein into the story.

Lieberman's approach is important for the philosophy of history because it leads us to ask different questions about historical causation and historical time. And it provides important new thinking about how to approach the nexus between regional history and global history.

Strange parallels

Victor Lieberman uses the phrase, "strange parallels," as the title for his two-volume study of Southeast Asian history (Strange Parallels: Volume 1, Integration on the Mainland: Southeast Asia in Global Context, c. 800-1830). Besides offering a highly expert history of Burma and its many kingdoms between 800 and 1830, Lieberman poses a fascinating and novel question: how can we explain the substantial historical parallels that existed between Burma and various parts of Europe, including especially France and Russia? He writes:

In fact, in mainland Southeast Asia as well as in France, the late 18th and early 19th centuries ended the third and inaugurated the last of four roughly synchronized cycles of political consolidation that together spanned the better part of a millenium. (2)

fig. 1.2. Territorial consolidation (p. 4)

The figure illustrates the kind of synchrony that Lieberman is highlighting -- over a sweep of some thousand years, there is a rough-and-ready correspondence in the patterns of territorial consolidation that existed in Burma and France.

Lieberman poses the crucial historical question in these terms: "Why should distant regions, with no obvious religious or material links, have experienced more or less coordinated cycles? If we discount coincidence, what hitherto invisible ties could have spanned the continents?" (2)

Apriori there appear to be only a small number of logically distinct possibilities that could explain the fact that patterns of variation are synchronized between A and B. (1) It may be that there is a causal linkage from A to B such that A's variations stimulate subsequent variations in B. (2) It may be that there is a common cause C whose variation simultaneously causes variation in both A and B. Global climate variation might be such an example. (3) It may be that both A and B are running through their variations according to the same internal clock, with the result that their variations are synchronized without causal interaction -- like two clocks ringing out the hours in tandem or two adolescent children going through roughly the same developmental stages at roughly the same time. (4) It may be that the observed synchrony is simple coincidence, with no causal explanation whatsoever.

So far as I can see, this exhausts the logical possibilities; there is no fifth possibility.

To further complicate the picture, Lieberman points out that there were other regions of the world where these patterns of consolidation did not occur, or did so on a very different timeline. So we can exclude the idea that there was some common global cause leading to simultaneous pulses of consolidation; rather, Southeast Asia and Western Europe were synchronized, but India was not.

Lieberman's explanation of this observed historical synchrony goes along these lines. He believes that both internalist and externalist approaches have a role to play. The internal historical dynamics of the state systems in Burma and Western Europe were governed by particular local factors. But they each created a tendency towards consolidation of land and power. And external factors provided periodic "pulses" that served to synchronize these internal patterns of development. So the effects of an external factor -- maritime trade -- pushed both Western Europe and Burma into extended periods of state formation and consolidation. This story combines (3) and (2) above: local processes that are developing according to their own imperatives, and occasional system-wide pulses that bring these local processes into synchrony. And the explanation allows Lieberman to place the intellectual frameworks of both Tilly and Wallerstein into the story.

Lieberman's approach is important for the philosophy of history because it leads us to ask different questions about historical causation and historical time. And it provides important new thinking about how to approach the nexus between regional history and global history.

Strange parallels

Victor Lieberman uses the phrase, "strange parallels," as the title for his two-volume study of Southeast Asian history (Strange Parallels: Volume 1, Integration on the Mainland: Southeast Asia in Global Context, c. 800-1830). Besides offering a highly expert history of Burma and its many kingdoms between 800 and 1830, Lieberman poses a fascinating and novel question: how can we explain the substantial historical parallels that existed between Burma and various parts of Europe, including especially France and Russia? He writes:

In fact, in mainland Southeast Asia as well as in France, the late 18th and early 19th centuries ended the third and inaugurated the last of four roughly synchronized cycles of political consolidation that together spanned the better part of a millenium. (2)

fig. 1.2. Territorial consolidation (p. 4)

The figure illustrates the kind of synchrony that Lieberman is highlighting -- over a sweep of some thousand years, there is a rough-and-ready correspondence in the patterns of territorial consolidation that existed in Burma and France.

Lieberman poses the crucial historical question in these terms: "Why should distant regions, with no obvious religious or material links, have experienced more or less coordinated cycles? If we discount coincidence, what hitherto invisible ties could have spanned the continents?" (2)

Apriori there appear to be only a small number of logically distinct possibilities that could explain the fact that patterns of variation are synchronized between A and B. (1) It may be that there is a causal linkage from A to B such that A's variations stimulate subsequent variations in B. (2) It may be that there is a common cause C whose variation simultaneously causes variation in both A and B. Global climate variation might be such an example. (3) It may be that both A and B are running through their variations according to the same internal clock, with the result that their variations are synchronized without causal interaction -- like two clocks ringing out the hours in tandem or two adolescent children going through roughly the same developmental stages at roughly the same time. (4) It may be that the observed synchrony is simple coincidence, with no causal explanation whatsoever.

So far as I can see, this exhausts the logical possibilities; there is no fifth possibility.

To further complicate the picture, Lieberman points out that there were other regions of the world where these patterns of consolidation did not occur, or did so on a very different timeline. So we can exclude the idea that there was some common global cause leading to simultaneous pulses of consolidation; rather, Southeast Asia and Western Europe were synchronized, but India was not.

Lieberman's explanation of this observed historical synchrony goes along these lines. He believes that both internalist and externalist approaches have a role to play. The internal historical dynamics of the state systems in Burma and Western Europe were governed by particular local factors. But they each created a tendency towards consolidation of land and power. And external factors provided periodic "pulses" that served to synchronize these internal patterns of development. So the effects of an external factor -- maritime trade -- pushed both Western Europe and Burma into extended periods of state formation and consolidation. This story combines (3) and (2) above: local processes that are developing according to their own imperatives, and occasional system-wide pulses that bring these local processes into synchrony. And the explanation allows Lieberman to place the intellectual frameworks of both Tilly and Wallerstein into the story.

Lieberman's approach is important for the philosophy of history because it leads us to ask different questions about historical causation and historical time. And it provides important new thinking about how to approach the nexus between regional history and global history.

System tendencies?

A central theme of many of the posts here is the contingency, heterogeneity, and path dependency of social processes. I used the metaphor of a "constrained random walk" in an earlier posting to characterize many social processes. This figure is intended to stand in contrast to the idea of an inevitable development towards an optimum or equilibrium point, on the one hand, or the idea of an inevitable system failure, on the other.

The idea here is this: from starting point A, there are numerous possible states of affairs Oi that might be reached over an extended period of time. There is no sense in which the course from A to the actual historical outcome Om is inevitable or unique. (From the starting point of Europe in 1910, including the social, political, and economic realities of the nations of Europe, multiple outcomes were accessible by the time of 1920: exhausting war, emergence of new and effective international organizations that sustained the peace, inspired just-in-time diplomacy bringing hostilities to an early termination, ...). Each of the pathways leading from A to Oi might be individually explicable, in terms of the situations of structure and agency that were present during the period of development. Virtually every point in the "space" of outcomes would be accessible, although some outcomes might be substantially less likely than others. Along the way there are likely to be cul-de-sacs; but in the aggregate, the space of possible outcomes from many historical starting points covers the full sphere of possibilities. Putting the point crudely, you can get anywhere from anywhere.

This conception emphasizes deep contingency in social change. But what about the symmetrical facts of "constraint" and "imperative" -- the limitations imposed by existing institutions and organizations at any specific stage and the positive impulses to change that are often embodied in the incentive structures of existing institutions? Is the contingency of social events to some extent reduced by the relative durability of existing core social institutions? Is there such a thing as a "logic of institutions" that is embodied in a particular configuration of core social institutions, with the result that societies embodying these institutions will be most likely to develop in one way rather than another?

This description lies at the heart of Marx's analysis of social systems as modes of production. Marx believed that the core institutions that defined the property system, the system of labor control, and the distribution of wealth have deep effects on individual agency, leading and constraining agents to behave in ways that lead in the aggregate to certain kinds of social outcomes. Modes of production have system tendencies that can be inferred from their basic institutional features. A particularly clear example is his analysis of the "law" of the falling rate of profit within capitalism: firms are required to maximize profits; they have the opportunity of introducing capital-intensive technologies that lower costs, thereby increasing profits in the short run; competition with other profit-maximizing firms pushes prices down to the new cost of production; the rising capital-labor ratio in industry creates a falling rate of profit. So capitalism embodies a system tendency towards a falling rate of profit over time. Similar reasoning underlies Marx's prediction of financial crises within capitalism. (See an earlier posting on Marx's conception of capitalism.)

And in fact, if we could make two assumptions, then Marx's reasoning about the tendencies of capitalism would be very compelling: the assumption that the core economic institutions are fixed and unchanging, and the assumption that there are no other social-political-economic institutions in play that might serve as resources for policies and actions that would offset the predicted tendencies of capitalism. However, neither of these assumptions is correct. The institutions of any major social order -- feudalism, the Chinese agrarian economy, capitalism, state socialism -- are always the composite of a vast number of lower-level institutions; and these lower-level institutions are usually in a state of flux. So the core institutions are not fixed and unchanging. The traditional Chinese agrarian economy was remarkably resilient in face of a range of deep challenges over centuries; adjustment of basic social institutions permitted Chinese society to cope better with environmental and international circumstances than a modeled Chinese economy would have predicted.

Second, even more fundamentally, a society is not simply a "mode of production," constituted by an economic structure. Rather, there are a range of other, equally fundamental institutions and practices -- cultural, political, legal, community-based and national -- through which resourceful agents attempt to solve personal or social problems at various points in time. So the "logic" of the economic institutions is only one part of the overall social trajectory; instead, we have the strategic interaction and aggregation of political, cultural, social, demographic, and legal institutions that complement and offset the workings of the economic structure. And further, we can correctly say that each of these aspects of social organization has its own "system tendencies." Elected legislatures have a logic that derives from the calculations of political self-interest of the legislators, community-based organizations have their own logic, various demographic regimes have their own tendencies (for example, the favoring of boy children produces skewed sex ratios that have negative political effects), and so forth.

So the tentative conclusion that I draw from these various considerations is, once again, to give the nod to contingency while recognizing the partial imperatives created by the various sets of core institutions that are embodied in a society at a given time. Structures do of course constrain agents. But structures interact with each other, leading to surprising results. And structures change in response to a variety of causes, including the strategic efforts of agents to modify them. So the upshot is, once again, that we should expect a high degree of contingency in outcomes over extended periods of historical time. Historical experience may well support the discovery that "capitalism creates a tendency towards X" or "fascist politics create a tendency towards Y". To that extent, there are "system tendencies". But it is rare for one particular sub-system (property relations, electoral system, demographic regime) to dominate the overall historical trajectory. And so the system tendencies of one partial set of core institutions rarely become the system tendencies of the overall social whole.

System tendencies?

A central theme of many of the posts here is the contingency, heterogeneity, and path dependency of social processes. I used the metaphor of a "constrained random walk" in an earlier posting to characterize many social processes. This figure is intended to stand in contrast to the idea of an inevitable development towards an optimum or equilibrium point, on the one hand, or the idea of an inevitable system failure, on the other.

The idea here is this: from starting point A, there are numerous possible states of affairs Oi that might be reached over an extended period of time. There is no sense in which the course from A to the actual historical outcome Om is inevitable or unique. (From the starting point of Europe in 1910, including the social, political, and economic realities of the nations of Europe, multiple outcomes were accessible by the time of 1920: exhausting war, emergence of new and effective international organizations that sustained the peace, inspired just-in-time diplomacy bringing hostilities to an early termination, ...). Each of the pathways leading from A to Oi might be individually explicable, in terms of the situations of structure and agency that were present during the period of development. Virtually every point in the "space" of outcomes would be accessible, although some outcomes might be substantially less likely than others. Along the way there are likely to be cul-de-sacs; but in the aggregate, the space of possible outcomes from many historical starting points covers the full sphere of possibilities. Putting the point crudely, you can get anywhere from anywhere.

This conception emphasizes deep contingency in social change. But what about the symmetrical facts of "constraint" and "imperative" -- the limitations imposed by existing institutions and organizations at any specific stage and the positive impulses to change that are often embodied in the incentive structures of existing institutions? Is the contingency of social events to some extent reduced by the relative durability of existing core social institutions? Is there such a thing as a "logic of institutions" that is embodied in a particular configuration of core social institutions, with the result that societies embodying these institutions will be most likely to develop in one way rather than another?

This description lies at the heart of Marx's analysis of social systems as modes of production. Marx believed that the core institutions that defined the property system, the system of labor control, and the distribution of wealth have deep effects on individual agency, leading and constraining agents to behave in ways that lead in the aggregate to certain kinds of social outcomes. Modes of production have system tendencies that can be inferred from their basic institutional features. A particularly clear example is his analysis of the "law" of the falling rate of profit within capitalism: firms are required to maximize profits; they have the opportunity of introducing capital-intensive technologies that lower costs, thereby increasing profits in the short run; competition with other profit-maximizing firms pushes prices down to the new cost of production; the rising capital-labor ratio in industry creates a falling rate of profit. So capitalism embodies a system tendency towards a falling rate of profit over time. Similar reasoning underlies Marx's prediction of financial crises within capitalism. (See an earlier posting on Marx's conception of capitalism.)

And in fact, if we could make two assumptions, then Marx's reasoning about the tendencies of capitalism would be very compelling: the assumption that the core economic institutions are fixed and unchanging, and the assumption that there are no other social-political-economic institutions in play that might serve as resources for policies and actions that would offset the predicted tendencies of capitalism. However, neither of these assumptions is correct. The institutions of any major social order -- feudalism, the Chinese agrarian economy, capitalism, state socialism -- are always the composite of a vast number of lower-level institutions; and these lower-level institutions are usually in a state of flux. So the core institutions are not fixed and unchanging. The traditional Chinese agrarian economy was remarkably resilient in face of a range of deep challenges over centuries; adjustment of basic social institutions permitted Chinese society to cope better with environmental and international circumstances than a modeled Chinese economy would have predicted.

Second, even more fundamentally, a society is not simply a "mode of production," constituted by an economic structure. Rather, there are a range of other, equally fundamental institutions and practices -- cultural, political, legal, community-based and national -- through which resourceful agents attempt to solve personal or social problems at various points in time. So the "logic" of the economic institutions is only one part of the overall social trajectory; instead, we have the strategic interaction and aggregation of political, cultural, social, demographic, and legal institutions that complement and offset the workings of the economic structure. And further, we can correctly say that each of these aspects of social organization has its own "system tendencies." Elected legislatures have a logic that derives from the calculations of political self-interest of the legislators, community-based organizations have their own logic, various demographic regimes have their own tendencies (for example, the favoring of boy children produces skewed sex ratios that have negative political effects), and so forth.

So the tentative conclusion that I draw from these various considerations is, once again, to give the nod to contingency while recognizing the partial imperatives created by the various sets of core institutions that are embodied in a society at a given time. Structures do of course constrain agents. But structures interact with each other, leading to surprising results. And structures change in response to a variety of causes, including the strategic efforts of agents to modify them. So the upshot is, once again, that we should expect a high degree of contingency in outcomes over extended periods of historical time. Historical experience may well support the discovery that "capitalism creates a tendency towards X" or "fascist politics create a tendency towards Y". To that extent, there are "system tendencies". But it is rare for one particular sub-system (property relations, electoral system, demographic regime) to dominate the overall historical trajectory. And so the system tendencies of one partial set of core institutions rarely become the system tendencies of the overall social whole.

System tendencies?

A central theme of many of the posts here is the contingency, heterogeneity, and path dependency of social processes. I used the metaphor of a "constrained random walk" in an earlier posting to characterize many social processes. This figure is intended to stand in contrast to the idea of an inevitable development towards an optimum or equilibrium point, on the one hand, or the idea of an inevitable system failure, on the other.

The idea here is this: from starting point A, there are numerous possible states of affairs Oi that might be reached over an extended period of time. There is no sense in which the course from A to the actual historical outcome Om is inevitable or unique. (From the starting point of Europe in 1910, including the social, political, and economic realities of the nations of Europe, multiple outcomes were accessible by the time of 1920: exhausting war, emergence of new and effective international organizations that sustained the peace, inspired just-in-time diplomacy bringing hostilities to an early termination, ...). Each of the pathways leading from A to Oi might be individually explicable, in terms of the situations of structure and agency that were present during the period of development. Virtually every point in the "space" of outcomes would be accessible, although some outcomes might be substantially less likely than others. Along the way there are likely to be cul-de-sacs; but in the aggregate, the space of possible outcomes from many historical starting points covers the full sphere of possibilities. Putting the point crudely, you can get anywhere from anywhere.

This conception emphasizes deep contingency in social change. But what about the symmetrical facts of "constraint" and "imperative" -- the limitations imposed by existing institutions and organizations at any specific stage and the positive impulses to change that are often embodied in the incentive structures of existing institutions? Is the contingency of social events to some extent reduced by the relative durability of existing core social institutions? Is there such a thing as a "logic of institutions" that is embodied in a particular configuration of core social institutions, with the result that societies embodying these institutions will be most likely to develop in one way rather than another?

This description lies at the heart of Marx's analysis of social systems as modes of production. Marx believed that the core institutions that defined the property system, the system of labor control, and the distribution of wealth have deep effects on individual agency, leading and constraining agents to behave in ways that lead in the aggregate to certain kinds of social outcomes. Modes of production have system tendencies that can be inferred from their basic institutional features. A particularly clear example is his analysis of the "law" of the falling rate of profit within capitalism: firms are required to maximize profits; they have the opportunity of introducing capital-intensive technologies that lower costs, thereby increasing profits in the short run; competition with other profit-maximizing firms pushes prices down to the new cost of production; the rising capital-labor ratio in industry creates a falling rate of profit. So capitalism embodies a system tendency towards a falling rate of profit over time. Similar reasoning underlies Marx's prediction of financial crises within capitalism. (See an earlier posting on Marx's conception of capitalism.)

And in fact, if we could make two assumptions, then Marx's reasoning about the tendencies of capitalism would be very compelling: the assumption that the core economic institutions are fixed and unchanging, and the assumption that there are no other social-political-economic institutions in play that might serve as resources for policies and actions that would offset the predicted tendencies of capitalism. However, neither of these assumptions is correct. The institutions of any major social order -- feudalism, the Chinese agrarian economy, capitalism, state socialism -- are always the composite of a vast number of lower-level institutions; and these lower-level institutions are usually in a state of flux. So the core institutions are not fixed and unchanging. The traditional Chinese agrarian economy was remarkably resilient in face of a range of deep challenges over centuries; adjustment of basic social institutions permitted Chinese society to cope better with environmental and international circumstances than a modeled Chinese economy would have predicted.

Second, even more fundamentally, a society is not simply a "mode of production," constituted by an economic structure. Rather, there are a range of other, equally fundamental institutions and practices -- cultural, political, legal, community-based and national -- through which resourceful agents attempt to solve personal or social problems at various points in time. So the "logic" of the economic institutions is only one part of the overall social trajectory; instead, we have the strategic interaction and aggregation of political, cultural, social, demographic, and legal institutions that complement and offset the workings of the economic structure. And further, we can correctly say that each of these aspects of social organization has its own "system tendencies." Elected legislatures have a logic that derives from the calculations of political self-interest of the legislators, community-based organizations have their own logic, various demographic regimes have their own tendencies (for example, the favoring of boy children produces skewed sex ratios that have negative political effects), and so forth.

So the tentative conclusion that I draw from these various considerations is, once again, to give the nod to contingency while recognizing the partial imperatives created by the various sets of core institutions that are embodied in a society at a given time. Structures do of course constrain agents. But structures interact with each other, leading to surprising results. And structures change in response to a variety of causes, including the strategic efforts of agents to modify them. So the upshot is, once again, that we should expect a high degree of contingency in outcomes over extended periods of historical time. Historical experience may well support the discovery that "capitalism creates a tendency towards X" or "fascist politics create a tendency towards Y". To that extent, there are "system tendencies". But it is rare for one particular sub-system (property relations, electoral system, demographic regime) to dominate the overall historical trajectory. And so the system tendencies of one partial set of core institutions rarely become the system tendencies of the overall social whole.

Continuity

Throughout much of our social experience we expect continuity: tomorrow will be pretty similar to today, and when changes occur they will be small and gradual. We expect our basic institutions -- economic, social, and political -- to maintain their core characteristics over long periods of time. We expect social attitudes and values to change only slowly, through gradual evolution rather than abrupt transformation. And we expect the same of a range of social conditions -- for example, highway safety, crime rates, teen pregnancy rates, and similar social features.

It is evident that this expectation of gradual, continuous change is not always a valid guide to events. Abrupt, unexpected events occur -- revolutions, mass cultural changes like the 1960s, sweeping political and legislative changes along the lines of the Reagan revolution. And of course we have the current example of abrupt declines in financial markets -- see the graph of the Dow Jones Industrial Average for the week of September 23-30, 2008 below. So the expectation of continuity sometimes leads us astray. But continuity is probably among our most basic heuristic assumptions about the future when it comes to our expectations about the social world and our plans for the future.

The deeper question is an ontological one: what features of social causation and processes would either support or undermine the expectation of continuity? We can say quite a bit about the features of continuity and discontinuity in physical systems; famously, "non-linearities" occur in some physical systems that lead to singularities and discontinuities, but many physical systems are safely linear and continuous all the way down. And these mathematical features follow from the fundamental physical mechanisms that underlie physical systems. But what about the social world?

Take first the stability of large social and political institutions. Is there a reason to expect that major social and political institutions will retain their core features in face of disturbing influences? Consider for example the SEC as a financial regulatory institution; the European Union as a multinational legislative body; or a large health maintenance organization. Here institutional sociologists have provided a number of important insights. First, institutions often change through the accumulation of a myriad of small adaptations in different locations within the institution. This is a process that is likely to give rise to slow, continuous, gradual change for the institution as a whole; and this is continuous behavior. Second, though, institutional sociologists have identified important internal forces that work actively to preserve the workings of the institution: the stakeholders who benefit from the current arrangements. Stakeholders are given incentives to actively reinforce and preserve the current institutional arrangements -- the status quo. Both of these factors suggest that institutional change will often be slow, gradual, and continuous.

Consider next the ways in which attitudes and values change in a population. Here it is plausible to observe that individuals change their attitudes and values slowly, through exposure to other individuals and behaviors. And the attitudes and values of a new generation are usually transmitted through processes that are highly decentralized -- again suggesting a slow and gradual process of change. So this suggests that changes in attitudes and values might behave analogously to the spread of a pathogen through a population -- with a slow and continuous spread of "contagion" resulting in a gradual change in population attitudes.

Consider last the example of social measures such as crime rates or teen pregnancy rates. If we take it as a premise that crime and teen pregnancy are influenced by social factors that in turn influence the behavior of individuals, and if we take it that these background social factors change slowly and continuously -- then it is credible to reason that the aggregate measures of the associated behaviors will change slowly and continuously as well. The reasoning here is probabilistic: when large numbers of people with a specified set of background social psychologies are exposed to common environmental circumstances, then it is plausible to predict that the average rate of teen pregnancy will remain fairly steady if the background circumstances remain steady.

These are all reasons for expecting a degree of stability and continuity in social arrangements and social behavior. But before we conclude that the social world is a continuous place, consider this: We also have some pretty clear models of how social phenomena might occur in a dis-continuous fashion. Critical mass phenomena, tipping points, and catastrophic failures are examples of groups of social phenomena where we should expect discontinuities. The behavior of a disease in a population may change dramatically once a certain percentage of the population is infected (critical mass); a new slang expression ("yada yada yada") may abruptly change its frequency of useage once a certain number of celebrities have adopted it (tipping point); a civic organization may be stretched to the breaking point by the addition of new unruly members and may suddenly collapse or mutate. (The hypothesis of punctuated equilibrium brings this sort of discontinuity into Darwinian theory of evolution.)

So there are some good foundational reasons for expecting a degree of continuity in the social environment; but there are also convincing models of social behavior that lead to important instances of discontinuous outcomes. This all seems to lead to the slightly worrisome piece of advice: don't bet on the future when the stakes are high. Stock markets collapse; unexpected wars occur; and previously harmonious social groups fall into fratricidal violence. And there is no fool-proof way of determining whether a singularity is just around the corner.