Meso powers and causal mechanisms

I've argued in earlier posts for several ideas:

1. Meso-level social structures have causal powers.
2. Meso-level social structures must have microfoundations.
3. Causal relations are carried out by causal mechanisms.

Are these claims consistent with each other?  An earlier post argues for the consistency of (1) and (2).  Here I will address the relation between (1) and (3): what kinds of causal mechanisms are available to mediate the causal powers of meso-level structures? Are there meso-level mechanisms as well as meso-level causes?  Or are the mechanisms that mediate meso causal powers themselves necessarily located at the micro level?

It is evident that there are micro-level mechanisms for meso-level causal powers. The mechanisms of a run on the bank or a self-fulfilling prophecy are both micro-level; they show how a meso-level event disaggregates onto the beliefs and actions of the individuals involved, leading to collective behavior that results in the meso-level effect. These are This is exactly the kinds of mechanism that analytical sociologists, including Thomas Schelling, want to be the exclusive kind of causation in the social realm. So the hard question is this: Are there meso-level causal mechanisms?

I addressed one aspect of this question in an earlier post, where I considered whether causal mechanisms can be complex and multi-staged.  There I focused on the idea that most theories of causal mechanisms require that there be a reasonably strong regularity between input and output.  This implies that a multi-step causal process will probably not qualify as a mechanism, because the intervening causal steps will imply a low association between initial condition and output condition.  (See the post for more details.)  And this in turn implies that a social mechanism needs to consist of one step: the instigating condition occurs and then the output condition occurs. The diagram illustrates the point. Scenario I represents a single-step causal mechanism; scenario II represents a three-step causal process composed of three component mechanisms.  Scenario II does not qualify as a mechanism itself, because the compound probability of D given A is only 50%.

So this would seem to answer the question for the case in which the putative meso-level causal mechanism involves multiple steps of causation. For example: {[Distracting work environment] => [low productivity] => [low profits] => [downsizing]} is a multiple-step causal process entirely at the meso level; but it doesn't establish a meso-level mechanism {[Distracting work environment] => [downsizing]} because the intervening steps imply new contingencies and a subsequent low conditional probability between antecedent and consequent.

There is another possible case to consider as well, however: the case in which a given meso-level structure or occurrence itself gives rise with high probability to a given meso-level result.  Are there such examples?

It would appear that there are.  Social isolation (referred to in an earlier post) is a meso-level characteristic of a population.  And Alford Young argues that decreasing social isolation causes rising inter-group hostility, another meso-level characteristic of a population.  This seems like a clear and uncontroversial example of a meso-meso causal link that is also a meso-level causal mechanism. It looks like Scenario I above.  Moreover, this mechanism can be employed in explanations of more complex social events like race rebellions.  It would seem that there are similar examples in the work of Robert Sampson on neighborhood effects (link).

And here is a third possibility. A meso-level structure S's causal powers may result from the causal powers of its component systems Ti, and the causal mechanisms that embody the causal powers of S may be found at the level of mechanisms at the level of Ti.  For example, a certain type of police organization S may have a high level of corruption C among its street officers.  So S has the causal power to bring about C. The mechanisms that establish this power may reside at a lower level of organization: the processes for giving assignments and the processes for checking incident reports. The diagram might look something like this.

The dashed line indicates the causal power. The solid arc lines on the left indicate "composition". The solid arrows indicate meso-meso causal mechanisms.  And the dotted lines indicate the aggregate consequences of "poor orientation to goals" and "weak incentives for conformance", which is an elevated level of officer corruption. So the meso-level power depends on sub-meso level mechanisms and actor-level mechanisms.

So the conclusion I'd like to tentatively offer is this: Meso-level causal powers are created as a consequence of specific causal mechanisms triggered by the properties and changes of the meso-level structure. Those mechanisms may be at the actor level; they may be at a sub-meso level; or they may be at the meso level.

Microfoundations and meso causation

I take the view that social causation requires microfoundations. And I hold that meso causal explanations are legitimate. How are these two views compatible?

The key is the role that we expect reasoning about micro-level events to play in the explanation itself. The various versions of methodological individualism -- microeconomics, analytical sociology, Elster's theories of explanation, and the model of Coleman's boat -- presume that explanation needs to invoke the story of the micro level events as part of the explanation. The microfoundations-meso explanation perspective requires that we be confident that these micro-level events exist and work to compose the meso level; but it does not require that the causal argument incorporates a reconstruction of the pathway through the individual level in order to have a satisfactory explanation.

Putting the methodological individualist model of explanation crudely, we get something like this:

Institution {I} shapes individuals' desires, beliefs, and passions {Ai}; individuals with these features of agency constitute the micro level; the tools of game theory, agent-based modeling, microeconomics, etc., allow us to aggregate the behavior of these individuals back to the macro level, in a new state of the macro level {O}.

The" meso-causal with microfoundations" view goes something like this.

Institution {I} has causal power P to influence future states of social aggregates; {I} occurs leading to P.
And, outside the explanation itself, we have:
[Institution I's causal powers have micro foundations along these lines: ...]

So when Michael Mann describes the effects of paramilitary organizations in Germany in the 1920s, he relies on a number of assertions about the causal powers of these organizations when introduced into the social circumstances of the 1920s. He is prepared to say how these effects work--so he satisfies the microfoundations requirement. But his explanation is a meso-level one, proceeding from the meso-level causal properties of paramilitary organizations to another set of meso-level effects (link).

When we explain why the tea kettle begins to whistle, we provide a meso-level explanation and we recognize the microfoundations that each step rests upon:

The kettle is filled with water.
The kettle is subject to a hot flame.
Water boils at 100 degrees centigrade.
Steam is produced at higher pressure than one atmosphere.
Steam exits through the spout, creating the whistle.

This is a meso level physical explanation with very well understood microfoundations, at the level of the molecular properties of H2O, its phase transitions, etc. And, of course, that molecular explanation itself has microfoundations. But here is the key point: the explanation at the level of heat, liquid, boiling point, and steam is perfectly satisfactory for many purposes. And it is scientifically satisfactory because we are confident that we understand the micro mechanisms that underlie each step of the argument. But we are not obliged to provide a molecule-level simulation of the situation in order to be satisfied that we have explained the whistling tea kettle.

Working sociologists offer explanations like Mann's on a regular basis. They identify what they take to be causal properties of social structures and institutions, and then draw out causal chains involving those causal properties. And often they are able to answer the follow-on question: how does that causal power work, in approximate terms, at the micro level? But answering that question is not an essential part of their argument. They do not in fact attempt to work through the agent-based simulation that would validate their general view about how the processes work at the lower level.

This account suggests an alternative diagram to Coleman's boat.



The diagram represents the meso-level claim that E1 and E3 jointly cause the occurrence of E2. The meso causal relation is represented as a single-directional orange arrow. The green arrows represent the microfoundations of each meso factor. These causal relations are bidirectional: individual actors are influenced by the meso factor, and their actions have influences on the meso factor. The yellow arrows, finally, represent inter-actor influences at the micro level: network relationships, alliances, communications channels, exemplary behavior, mobilization efforts, etc.

The diagram represents each of the causal linkages represented in the Coleman boat. But it calls out the meso-meso causal connection that Coleman prohibits in his analysis. And it replaces the idea that causation proceeds through the individual level, with the idea that each meso level factor has a set of actor-level microfoundations. But this is an ontological fact, not a prescription on explanation.

And, finally, it is self-evident that we can always ask a different question that looks more like Coleman's: how does the causal property of the meso factor work at the level of the actor? But this is a different question, and we aren't required to incorporate the resulting story into the meso-meso explanation.

Meso-foundational explanations

One of the catechismal ideas of analytical sociology is the microfoundations model of explanation: to explain a social fact we should provide an account of the microfoundations that produce it. That means identifying the facts about individual motivations and beliefs that lead them to behave in such a way as to bring about the social fact in question. Here I want to ask a deliberately provocative question: is it ever legitimate to look for a meso-foundational explanation?

There is an almost trivial answer to this question that is already implied by Coleman’s famous boat diagram (link): when we want to understand how actors came to have the motivations and beliefs that we have observed.

The local prevalence of Catholic values and practices is the causal factor that explains the distinctive mentality of French Catholic young people in Burgundy in the 1930s. Here we are proposing to give a meso- or macro-level account of a micro set of facts. As another example, we might account for the low percentage of stocks in the retirement plans of men in their 50s in 1970 by the mistrust of the stock market created in people who reached adulthood in the Great Depression. This too is a meso- to micro- explanation.

Are there other kinds of meso-foundational explanations? Can we provide satisfactory meso-level explanations of meso- or macro-level facts? Consider this possibility. Suppose we find that S&L institutions are less likely to become insolvent than large commercial banks. And suppose we find that the regulatory regimes governing S&Ls are more strict than those for commercial banks. The mechanism leading to a lower likelihood of insolvency is conveyed from "strict regulations" to "low likelihood of insolvency". (We can provide further underlying mechanisms, of the traditional microfoundational variety: officers of S&Ls understand the requirements of the regulatory regime; they prudently miminize the risk of civil or criminal penalties; and their institutions have a lower likelihood of insolvency.) This is a meso-level causal explanation of a meso-level fact, representing a causal relationship between one meso-level factor and another meso-level factor.

What about meso-foundational explanations of macro-level features? And symmetrically, what about macro-foundational explanations of meso- and micro-level features? Each of these pathways is possible. Consider a macro-level feature like “American males have an unusually strong identification with guns”. And suppose we offer a meso-level explanation of this widespread cultural value: “The shaping institutions of masculine cultural identity in a certain time and place (mass media, high school social life, popular fiction) inculcate and proliferate this feature of masculine identity.” This is a meso-level explanation of a macro-level feature. Moreover, we can also turn the explanatory lens around and explain the workings of the meso-level factors based on the pervasive macro-level factor: the prevailing male obsession with guns reinforces and reproduces the meso-level influences identified here.

The conclusion to be drawn from these observations is a bit disorienting. The examples imply that there is no “up” and “down” when it comes to explanatory primacy. Rather, social factors at each level can play an explanatory role in accounting for the features of facts at every level. Explanation does not necessarily proceed from “lower level” to higher level entities. "Descending", "ascending", and "lateral" causal explanations all have their place, and ascending (microfoundational) explanations have no special priority. Rather, the requirement that should be emphasized is that the adequacy of any explanation of a social fact depends on whether we have discovered the causal mechanisms that give rise to it. And causal mechanisms can operate at all levels of the social world.

The diagram at the top of the post, originally prepared to illustrate the idea of a "flat" social ontology, does a good job of illustrating the multi-directionality of social-causal mechanisms as well.

Social mechanisms and meso-level causes

(This post summarizes a paper I presented at the British Society for the Philosophy of Science Annual Meeting in 2012.)

Here and elsewhere I want to defend the theoretical possibility of attributing causal powers to meso-level social entities and structures.  In this I follow a number of philosophers and sociologists, including many critical realists (e.g. Roy Bhaskar, A Realist Theory of Science and Margaret Archer, Realist Social Theory: The Morphogenetic Approach) and also the recent thinking of Dave Elder-Vass (The Causal Power of Social Structures).  But I also defend the idea of an actor-centered sociology, according to which the substance of social phenomena is entirely made up of the actions, interactions, and states of mind of socially constituted individual actors.  Making out both positions, and demonstrating their consistency, is the work of this paper. I refer to this position as “relative explanatory autonomy” of the meso-level. This topic is of renewed interest because of the current influence and progress of analytical sociology (Peter Hedström, Dissecting the Social: On the Principles of Analytical Sociology; Hedström and Bearman, The Oxford Handbook of Analytical Sociology ; Peter Demeulenaere, Analytical Sociology and Social Mechanisms), which offers an emphatic “no” to the question; whereas critical realists are equally firm in defending an affirmative answer to the question.

My defense of meso-level causation is based on four ideas. First, the practice of sociologists justifies this claim, since sociologists do in fact make use of meso-meso claims.  They often do not attempt to provide vertical explanations from circumstances of the actor to meso- and macro-level outcomes; instead, they often provide horizontal explanations that explain one set of meso and macro outcomes on the basis of the causal powers of another set of meso and macro conditions or structures.  Second, sociology is a “special science” analogous to cognitive science, dependent on a set of causally linked entities at a lower level. Arguments offered for the relative explanatory autonomy of the higher-level theories are applicable to sociology as well. The basis for rejecting reductionism is well established here. Third, meso entities (organizations, institutions, normative systems) often have stable characteristics with regular behavioral consequences. This is illustrated with the example of organizations. Fourth, those entities must have microfoundations; we must be confident that there are individual behaviors at lower levels that support these macro characteristics.  But it is legitimate to draw out the macro-level effects of the macro-circumstance under investigation, without tracing out the way that effect works in detail on the swarms of actors encompassed by the case.   The requirement of microfoundations is not a requirement on explanation; it does not require that our explanations proceed through the microfoundational level. It is an ontological principle but not a methodological principle.  Rather, it is a condition that must be satisfied on prima facie grounds, prior to offering the explanation. (I refer to this as the "weak" requirement of microfoundations; link.)  In short, we are not obliged to trace out the struts of Coleman’s boat in order to provide a satisfactory macro- or meso-level explanation or mechanism.

Does the extended social world have causal powers?  Here are some reasons for thinking that it does.

First, working sociologists offer explanations that postulate meso-meso causal connections on a regular basis. They identify what they take to be causal properties of social structures and institutions, and then draw out causal chains involving those causal properties. And often they are able to answer the follow-on question: how does that causal power work, in approximate terms, at the micro level? But answering that question is not an essential part of their argument. They do not in fact attempt to work through the agent-based simulation that would validate their general view about how the processes work at the lower level.

This explanatory framework seems entirely reasonable in the social sciences.  It does not seem necessary to disaggregate every claim like “organizational deficiencies at the Bhopal chemical plant caused the devastating chemical spill” onto specific individual-level activities. We understand pretty well, in a generic way, what the microfoundations of organizations are, and it isn’t necessary to provide a detailed account in order to have a satisfactory explanation.  In other words, we can make careful statements about macro-macro and macro-meso causal relations without proceeding according to the logic of Coleman’s boat—up and down the struts. So one argument for the relative autonomy of meso-level causal claims is precisely the fact that good sociologists do in fact make credible use of such claims.

Second, there is a more general reason within the philosophy of the social sciences for being receptive to the idea of meso-meso social causes.  This derives from the arguments against reductionism in a range of the special sciences.  The idea of relative explanatory autonomy has been invoked by cognitive scientists against the reductionist claims of neuro-scientists. Of course cognitive mechanisms must be grounded in neurophysiological processes. But this doesn’t entail that cognitive theories need to be reduced to neurophysiological statements. Jerry Fodor introduced highly influential arguments against reductionism in “Special sciences and the disunity of science as a working hypothesis” (link).
Once we have reason to accept something like the idea of relative explanatory autonomy in the social sciences, we also have a strong basis for rejecting the exclusive validity of one particular approach to social explanation, the reductionist approach associated with methodological individualism, analytical sociology, and Coleman’s boat. Rather, social scientists can legitimately use explanations that call upon meso-level causal linkages without needing to reduce these to derivations from facts about individuals. And this implies the legitimacy of a fairly broad conception of methodological pluralism in the social sciences, constrained always by the requirement of weak microfoundations.

Third, we have good research-based reasons to maintain that meso-level social structures have causal powers. Consider organizations as paradigm examples of meso-level social structures. An organization is a social entity which possesses a degree of stability in functioning that can be studied empirically and theoretically. An organization consists of a structured group of individuals, often hierarchically organized, pursuing a relatively clearly defined set of tasks.  In the abstract, it is a set of rules and procedures that regulate and motive the behavior of the individuals who function within the organization. There are also informal practices within an organization that are not codified that have significant effects on the functioning of the organization (for example, the coffee room as a medium of informal communication, or the norm of covering for a co-worker’s absence).  Some of those individuals have responsibilities of oversight, which is a primary way in which the abstract rules of the organization are transformed into concrete patterns of activity by other individuals. Another behavioral characteristic of an organization is the set of incentives and rewards that it creates for participants in the organization. Often the incentives that exist were planned and designed to have specific effects on behavior of participants; by offering rewards for behaviors X, Y, Z, the organization is expected to produce a lot of X, Y, and Z. Sometimes, though, the incentives are unintended, created perhaps by the intersection of two rules of operation that lead to a perverse incentive leading to W.

Now we are in a position to address the central question here: do organizations have causal powers? It seems to me that the answer is yes, in fairly specific ways. The most obvious causal properties of an organization are bound up in the function of the organization. An organization is invented and developed in order to bring about certain social effects: operate and maintain a complex technology, reduce pollution or crime, distribute goods throughout a population, provide services to individuals, seize and hold territory, disseminate information. But the specifics of an organization also give rise to unintended consequences; these too contribute to the causal powers of the organization. All these effects occur as a result of the coordinated activities of people within the organization. When organizations work correctly they bring about one set of effects; when they break down they bring about another set of effects. Here we can think about organizations in analogy with technology components like amplifiers, thermostats, stabilizers, or surge protectors.

Finally, I too believe that there is a burden of proof that must be met in asserting a causal power or disposition for a social entity -- something like “the entity demonstrates an empirical regularity in behaving in such and such a way” or “we have good theoretical reasons for believing that X social arrangements will have Y effects.” And some macro concepts (e.g. State, Islam, market economy) are likely cast at too high a level to admit of such regularities. That is why I favor “meso” social entities as the bearers of social powers. As new institutionalists demonstrate all the time, one property regime elicits very different collective behavior from its highly similar cousin. And this gives the relevant causal stability criterion. Good examples include Robert Ellickson’s new-institutionalist treatment of Shasta County and liability norms and Charles Perrow’s treatment of the operating characteristics of technology organizations. In each case the microfoundations are easy to provide. What is more challenging is to show how these social causal properties interact in cases to create outcomes we want to explain.

So how does the micro-macro link look when we attempt to provide the idea of meso explanations with microfoundations?  The various versions of methodological individualism—microeconomics, analytical sociology, Elster’s theories of explanation, and the model of Coleman’s boat—presume that explanation needs to invoke the story of the micro level events as part of the explanation. The perspective offered here requires something quite different.  This position requires that we be confident that these micro-level events exist and work to compose the meso level; but it does not require that the causal argument incorporates a reconstruction of the pathway through the individual level in order to have a satisfactory explanation.  This account suggests an alternative diagram to Coleman’s boat.


The diagram represents each of the causal linkages represented in the Coleman boat. But it also calls out the meso-meso causal connection that Coleman prohibits in his analysis. And it replaces the idea that causation proceeds through the individual level, with the idea that each meso level factor has a set of actor-level microfoundations. But this is an ontological fact, not a prescription on explanation.
(Here is the full paper as presented at the British Society for the Philosophy of Science Annual Meeting in July 2012 at the University of Stirling.)

Are there meso-level social mechanisms?

It is fairly well accepted that there are social mechanisms underlying various patterns of the social world — free-rider problems, communications networks, etc. But the examples that come readily to mind are generally specified at the level of individuals. The new institutionalists, for example, describe numerous social mechanisms that explain social outcomes; but these mechanisms typically have to do with the actions that purposive individuals take within a given set of rules and incentives.

The question here is whether we can also make sense of the notion of a mechanism that takes place at the social level. Are there meso-level social mechanisms? (As always, it is acknowledged that social stuff depends on the actions of the actors.)

This question is analogous to two other similar issues in other special sciences:

• Are there information-system level causal mechanisms in human cognition?
• Are there cellular-level causal mechanisms in biological systems?

Or, to the contrary, are all mechanisms in sociology, cognition science, and biology properly understood to be carried out at the level of individuals, neurons, and biochemistry?

Here is my version of a definition of a causal mechanism (link):

A causal mechanism is (i) a particular configuration of conditions and processes that (ii) always or normally leads from one set of conditions C to an outcome O (iii) through the properties and powers of the events and entities in the domain of concern. 

And here is the definition offered by Doug McAdam, Sidney Tarrow, and Chuck Tilly in Dynamics of Contention:

Mechanisms are a delimited class of events that alter relations among specified sets of elements in identical or closely similar ways over a variety of situations. (kl 354)

We should begin by asking what it is that we are looking for. What would a meso-level mechanism look like?

Here is a start: it would be a linkage between two conditions or entities, each of which is itself a meso-level structure or entity. So a meso-level causal mechanism is one in which both C and O are meso-level entities or conditions and where C leads to O "always or normally".

Earlier I argued that meso-level entities possess causal powers: regular dispositions to produce specified effects, grounded in the substrate of social activity (link). If some of those effects O_i are themselves meso-level outcomes or structures, then our question here is answered. Any pair {C,O_i} is itself a meso-level causal mechanism. If, on the other hand, the causal powers of meso-level entities are restricted to changes in the behavior of individuals, then meso-level mechanisms do not exist.

McAdam, Tarrow, and Tilly address a very similar question in Dynamics of Contention, and they argue for what they call "relational mechanisms":

Relational mechanisms alter connections among people, groups, and interpersonal networks. Brokerage, a mechanism that recurs throughout Parts II and III of the book, we define as the linking of two or more previously unconnected social sites by a unit that mediates their relations with one another and/or with yet other sites. Most analysts see brokerage as a mechanism relating groups and individuals to one another in stable sites, but it can also become a relational mechanism for mobilization during periods of contentious politics, as new groups are thrown together by increased interaction and uncertainty, thus discovering their common interests. (kl 376)

Having formulated the question in these terms, it seems that we can provide a credible affirmative answer: it is possible to identify a raft of social explanations in sociology that represent causal assertions of social mechanisms linking one meso-level condition to another. Here are a few examples:

• Al Young: decreasing social isolation causes rising inter-group hostility (link)
• Michael Mann: the presence of paramilitary organizations makes fascist mobilization more likely (link)
• Robert Sampson: features of neighborhoods influence crime rates (link)
• Chuck Tilly: the availability of trust networks makes political mobilization more likely (link)
• Robert Brenner: the divided sovereignty system of French feudalism impeded agricultural modernization (link)
• Charles Perrow: legislative control of regulatory agencies causes poor enforcement performance (link)

We might also consider the possibility of compound meso-level mechanisms, in which M₁ produces M₂ which in turn produces M₃. Does the sequence also qualify as a mechanism? That depends on the strength of the relationships that exist at each link; if the conditional probabilities of the links fall low enough, then the compound probability of the chain is no longer sufficient to satisfy condition (ii) above ("initial condition normally leads to the outcome").

Essentially this question comes down to the tightness of the linkages that exist among the sub-components of social systems. If there are sub-components within bureaucracies that maintain their properties and are tightly linked to specified outcomes, then these can play a role within meso-level causal mechanism narratives. If, on the other hand, the effects of a given subcomponent of a social system vary widely over time and space, then that type of component does not play a useful role in a causal mechanisms analysis. So the question of how extensive meso-level causal mechanisms are is itself an empirical one; it depends on the specific features of the social world.

So it seems as though we can offer two related conclusions about the causal reality of meso-level entities: meso-level structures possess causal powers, and there are causal mechanisms that invoke meso-level entities as both input and output.

Are organizations emergent?

Do organizations have properties that are in some recognizable way independent from the behaviors and intentions of the individuals who inhabit them? In A New Social Ontology of Government I emphasized the ways in which organizations fail because of actor-level features: principal-agent problems, inconsistent priorities and goals across different working groups, strategic manipulation of information by some actors to gain advantage over other actors, and the like. With a nod to Fligstein and McAdam's theory of strategic action fields (link), I took an actor-centered approach to the workings (and dysfunctions) of organizations. I continue to believe that these are accurate observations about the workings of organizations and government agencies, but now that I've reoriented my thinking away from a strictly actor-centered approach to the social world (link), I'm interested in asking the questions about meso-level causes I did not ask in A New Social Ontology.

For example: 

(a) Are there relatively stable meso-level features of organizations that constrain and influence individual behavior in consistent ways that produce relatively stable meso-level outcomes? 

(b) Are there routine behaviors that are reproduced within the organization by training programs and performance audits that give rise to consistent patterns of organizational workings? 

(c) Are there external structural constraints (legal, environmental, locational) that work to preserve certain features of the organization's scheme of operations? 

It seems that the answer to each of these questions is "yes"; but this in turn seems to imply that organizations have properties that persist over time and through changes of personnel. They are not simply the result of the sum of the behaviors and mental states of the participants. These meso-level properties are subject to change, of course, depending on the behaviors and intentions of the individuals who inhabit the organization; but they are sometimes stable across extended periods of time and individual personnel. Or in other words, there seem to be meso-level features of organizations that are emergent in some moderate sense.

Here are possible illustrations of each kind of "emergent" property.

(a) Imagine two chemical plants Alpha and Beta making similar products with similar industrial processes and owned by different parent corporations. Alpha has a history of occasional fires, small explosions, and defective equipment, and it was also the site of a major chemical fire that harmed dozens of workers and neighbors. Beta has a much better safety record; fires and explosions are rare, equipment rarely fails in use, and no major fires have occurred for ten years. We might then say that Alpha and Beta have different meso-level safety characteristics, with Alpha lying in the moderate risk range and Beta in the low risk range. Now suppose that we ask an all-star team of industrial safety investigators to examine both plants, and their report indicates that Alpha has a long history of cost reduction plans, staff reductions, and ineffective training programs, whereas Beta (owned by a different parent company) has been well funded for staffing, training, and equipment maintenance. This is another meso-level property of the two plants -- production decisions guided by profitability and cost reduction at Alpha, and production decisions guided by both profitability and a commitment to system safety at Beta. Finally, suppose that our team of investigators conducts interviews and focus groups with staff and supervisors in the two plants, and finds that there are consistent differences between the two plants about the importance of maintaining safety as experienced by plant workers and supervisors. Supervisors at Alpha make it clear that they disagree strongly with the statement, "interrupting the production process to clarify anomalous temperature readings would be encouraged by the executives", whereas their counterparts at Beta indicate that they agree with the statement. This implies that there is a significant difference in the safety culture of the two plants -- another meso-level feature of the two organizations. All of these meso-level properties persist over decades and through major turnover of staff. Supervisors and workers come and go, but the safety culture, procedures, training, and production pressure persist, and new staff are introduced to these practices in ways that reproduce them. And -- this is the key point -- these meso-level properties lead to different rates of failure at the two plants over time, even though none of the actors at Alpha intend for accidents to occur. 

(b) This example comparing industrial plants with different safety rates also serves to answer the second question posed above about training and oversight. The directors and staff who conduct training in an industrial organization can have high commitment or low commitment to their work -- energetic and focused training programs or perfunctory and forgettable training programs -- and the difference will be notable in the performance of new staff as they take on their responsibilities. For example, training for control room directors may always emphasize the importance of careful annotation of the day's events for the incoming director on the next shift. But the training may be highly effective, resulting in informative documentation across shift changes; or it may be ineffective and largely disregarded. In most cases poor documentation does not lead to a serious accident; but sometimes it does. So organizations with effective training on procedures and operations will have a better chance of avoiding serious accidents. Alpha has weak training programs, while Beta has strong training programs (and each dedicates commensurate resources to training). Routine behaviors at Alpha lead to careless implementation of procedures, whereas routine behaviors at Beta result in attentive implementation, and as a result, Beta has a better safety performance record.

(c) What about the external influences that have an effect on the overall safety performance of an industrial plant? The corporate governance and ownership of the plant is plainly relevant to safety performance through the priorities it establishes for production, profitability, and safety. If the corporation's highest priority is profitability, then safety procedures and investments take the back seat. Local budget managers are pressed to find cost reductions, and staff positions and equipment devoted to safety are often the easiest category of budget reduction to achieve. On the other hand, if the corporation's guidance to plant executives is a nuanced set of priorities within which both production goals and safety goals are given importance, there is a better chance of preserving the investments in process inspectors, better measurement instruments, and on-site experts who can be called on to offer advice during a plant emergency. This differentiating feature of corporate priority-setting too is a meso-level property that contributes to the level of safety performance in a chemical plant, independent of the knowledge and intentions of local plant managers, directors, and workers.

These brief hypothetical examples seem to establish a fairly mundane form of "emergence" for organizational properties. They provide examples of causal independence of meso-level properties of organizations. And significantly, each of these meso-level features can be identified in case studies of important industrial failures -- the Boeing 737 Max (link), the Deepwater Horizon disaster (link), or the 2005 Texas City refinery explosion (link).

It may be noted that there are two related ideas here: the idea that a higher-level property is emergent from the properties of the constituent entities; and the idea that a higher-level feature may be causally persistent over time and over change of the particular actors who make up the social entity. The connection is this: we might argue that the causally persistent property at the meso-level is different in nature and effect from the causal properties (actions, behaviors, intentions) of the individuals who make up the organization. So causal persistence of meso-level properties demonstrates emergence of a sort.

Are there meso-level social causes?

Social structures and other social "things" are ontologically peculiar in some ways. Most especially, they are abstract, distributed, and non-material. We can't put a culturally dominant food aversion or a group prejudice in a box and weigh it. And yet many of us want to say that social structures are "real", not merely theoretical constructs.

One important aspect of something's being real is that it has causal powers: the specific properties of the thing bring about differences in the world on the behavior of other things. This is a version of the interventionist theory of causation associated with Jim Woodward: change something about C and you bring about a change in E (link).

So let's consider this question: Can meso-level social structures have meso-level effects?

Of course meso-level structures have effects -- on individuals. The fact that there are laws and enforcement mechanisms governing highway speed has some effect on drivers' behavior. The question here is whether it is legitimate to postulate causal powers for structures whose effects are realized in other meso-level structures. And I want to explore the affirmative answer to the question: it is legitimate and coherent to assert meso-meso causal interactions, and we sometimes have empirical evidence to support such assertions.

(It would be possible, of course, to take the view that social structures are epiphenomenal and have no causal properties whatsoever. On that approach, what seems to be the effect of the legal system on individual behavior is really just the aggregate effect of the many individuals involved in the legal system. I don't find this view at all compelling, however.)

My question is relevant to two groups of sociological theorists, each of whom thinks the answer is trivial and obvious -- but in opposite directions. The new methodological individualists, represented by analytical sociology, think the answer is trivially "no", because social causation proceeds always and exclusively through actions and interactions of individuals (link). This is the fundamental idea underlying Coleman's Boat as a model of the relationship between macro and micro.  And a range of anti-individualists -- Giddens, Elder-Vass, Archer -- believe it is self evident from everyday experience that causal structures do have causal powers, and that it is a waste of time to defend the notion (link). It is obvious.

My position is a precarious one. On the one hand I advocate an actor-centered approach to sociology and the social sciences. I defend the idea that social claims need microfoundations in a specific (weak) sense. And on the other hand I believe that structures have a degree of stability that permits us to couch causal claims in terms of those structures directly, rather than needing to supplement those claims with disaggregated foundations at the level of the individual. So I argue for the idea that we can sometimes regard causal powers of social entities as "relatively autonomous" from individual-level facts.

By meso-level structures I mean to refer to things like these:

• National Science Foundation
• Nuclear Regulatory Commission
• IBM corporation
• AFL-CIO
• German paramilitary organizations 1930
• German ideology of cultural despair 1910
• Islamic norms of Zakat
• ...

In each case there are numerous actors assigned to roles, governed by rules defining their activities, and leading to a certain kind of functioning in the broader social environment.

Generically I would define a meso-level structure as --

A composite of individuals and roles that incorporates a set of rules and norms for internal and external actors, and that possesses procedures of inculcation and enforcement through which internal and external actors are brought to comply with the rules and norms (to some degree).

I would define a normative system as ...

a set of rules, norms, and expectations embodied in a population of actors and meeting a threshold level of success in coordinating and constraining behavior.

We have a number of sociological concepts that capture social items at this level: organization, bureaucracy, institution, normative community, social network, communications system, legal system, civil war, military coup, advocacy group.

It is evident that social entities often incorporate elements of several of these kinds of things. Organizations and structures often incorporate or depend upon normative systems, and normative systems often generate organizations and institutions that convey their impact to the young and adult actors.
What about other mid-level social nouns -- ethnic group, electorate, financial crisis, ...? These strike me as being compounds of a miscellaneous set of social things -- there are bits of organizations, normative systems, affinity groups, and social networks in each of them. The concept of assemblage seems to fit these nouns well.

The "meso" qualifier is a bit more difficult to specify. It is intended to focus our attention on mid-level social arrangements, between actors and global institutions like the US state, global Islam, and the world trading system. The intuitive idea is straightforward. These are the smaller-scale, lower-level social arrangements or units of which macro structures are composed. Bert Leuridan makes an effort to offer a more specific definition based on causal roles.

So I have a simple but important question in mind here. Is it ever legitimate to assert something like this:

• Meso structure X produced changes in meso structure Y,

without being obliged to demonstrate the individual-level pathways through which this effect is thought to have come about? Is a type 4 causal claim ever supportable (link)?

The question I am posing is related to the idea of the methodological individualism associated with James Coleman. Basically the idea propounded by Coleman and more recently by the analytical sociologists is that all social properties, including causal powers, work through the activities of individuals, and we need ideally to replace claims that appear to attribute causal powers to structures with theories that disaggregate these powers onto the patterned activities of individuals. This is a reductionist theory.

Other theorists, notably Dave Elder-Vass, want to assert that social structures have "emergent" properties and powers (link). An emergent property according to E-V, is one that is possessed by the aggregate but not by the composing units. On this account, there are causal properties of structures that cannot be represented as the aggregate effect of individual actors.

My own approach depends on a line of reasoning long familiar in the special sciences. It is anti-reductionist, in that it denies that we need to derive higher-level properties from lower-level properties. It accepts the compositional ontology: social structures are composed of individual actors. But it asserts explanatory autonomy for theoretical statements about mid-level mechanisms (link, link, link).

One particularly direct way of supporting the idea that structures have meso effects is to establish correlations at that level for a few examples. But this isn't the only way we establish causation in other areas of the sciences. We do experiments ("remove X and observe whether Y persists"), we analyze the outcomes of "natural" experiments, we do comparative studies, and we engage in process tracing of particular cases. We even engage in theoretical analysis to try to determine what causal powers a certain entity ought to be expected to have given its constitution.

So it seems that there is ample room for sociologists to assert and investigate the causal properties of social structures. And given appropriate attention to the principle of microfoundations, we have a social ontology that supports the legitimacy of such claims as well.

A related question is whether there are "mechanisms" that operate at the meso level, or whether all social mechanisms must operate at the individual level (as Hedstrom and the AS world believe).  I will return to this question.

Relative explanatory autonomy

In an earlier post I indicated a degree of disagreement with the premises of analytical sociology concerning the validity of methodological individualism (link). This disagreement comes down to three things.

First, for reasons I've referred to several times here and elsewhere (link), I prefer to refer to methodological localism rather than methodological individualism.

This theory of social entities affirms that there are large social structures and facts that influence social outcomes. But it insists that these structures are only possible insofar as they are embodied in the actions and states of socially constructed individuals. The “molecule” of all social life is the socially constructed and socially situated individual, who lives, acts, and develops within a set of local social relationships, institutions, norms, and rules. (link)

I believe that the ideas of localism and socially constructed, socially situated actors do a better job of capturing the social molecule that underlies larger social processes than the simple idea of an "individual". Structural individualism seems to come to a similar idea, but less intuitively.

Second, the requirement of providing microfoundations for social assertions is preferable to methodological individualism because it is not inherently reductionist (link). A microfoundation is:

a specification of the ways that properties, structural features, and causal powers of a social entity are produced and reproduced by the actions and dispositions of socially situated individuals. (link)

We need to be confident that our theories and concepts about social structures, entities, and forces appropriately supervene upon facts about individuals; but we don't need to rehearse those links in every theory or explanation. In other words, we can make careful statements about macro-macro and macro-meso links without proceeding according to the logic of Coleman's boat -- up and down the struts. Jepperson and Meyer make this point in "Multiple Levels of Analysis and the Limitations of Methodological Individualisms" (link), and they offer an alternative to Coleman's macro-micro boat that incorporates explanations referring to meso-level causes (66).

Third, these points leave room for a meta-theory of relative explanatory autonomy for social explanations. The key insight here is that there are good epistemic and pragmatic reasons to countenance explanations at a meso-level of organization, without needing to reduce these explanations to the level of individual actors. Here is a statement of the idea of relative explanatory autonomy, provided by a distinguished philosopher of science, Lawrence Sklar, with respect to areas of the physical sciences:

Everybody agrees that there are a multitude of scientific theories that are conceptually and explanatorily autonomous with respect to the fundamental concepts and fundamental explanations of foundational physical theories. Conceptual autonomy means that there is no plausible way to define the concepts of the autonomous theories in terms of the concepts that we use in our foundational physics. This is so even if we allow a rather liberal notion of “definition” so that concepts defined as limit cases of the applicability of the concepts of foundational physics are still considered definable. Explanatory autonomy means that there is no way of deriving the explanatory general principles, the laws, of the autonomous theory from the laws of foundational physics. Once again this is agreed to be the case even if we use a liberal notion of “derivability” for the laws so that derivations that invoke limiting procedures are still counted as derivations. (link)

The idea of relative explanatory autonomy has been invoked by cognitive scientists against the reductionist claims of neuro-scientists. Of course cognitive mechanisms must be grounded in neurophysiological processes. But this doesn't entail that cognitive theories need to be reduced to neurophysiological statements. Sacha Bem reviews these arguments in "The Explanatory Autonomy of Psychology: Why a Mind is Not a Brain" (link). Michael Strevens summarizes some of these issues in "Explanatory Autonomy and Explanatory Irreducibility" (link). And here Geoffrey Hellman addresses the issues of reductionism and emergence in the special sciences in "Reductionism, Determination, Explanation".

These arguments are directly relevant to the social sciences, subject to several important caveats. First is the requirement of microfoundations: we need always to be able to plausibly connect the social constructs we hypothesize to the actions and mentalities of situated agents. And second is the requirement of ontological and causal stability: if we want to explain a meso-level phenomenon on the basis of the causal properties of other meso-level structures, we need to have confidence that the latter properties are reasonably stable over different instantiations. For example, if we believe that a certain organizational structure for tax collection is prone to corruption of the ground-level tax agents and want to use that feature as a cause of something else -- we need to have empirical evidence supporting the assertion of the corruption tendencies of this organizational form.

Explanatory autonomy is consistent with our principle requiring microfoundations at a lower ontological level. Here we have the sanction of the theory of supervenience to allow us to say that composition and explanation can be separated. We can settle on a level of meso or macro explanation without dropping down to the level of the actor. We need to be confident there are microfoundations, and the meso properties need to be causally robust. But if this is satisfied, we don't need to extend the explanation down to the actors.

Woven throughout this discussion are the ideas of reduction and emergence. An area of knowledge is reducible to a lower level if it is possible to derive the statements of the higher-level science from the properties of the lower level. A level of organization is emergent if it has properties that cannot be derived from features of its components. The strong sense of emergence holds that a composite entity sometimes possesses properties that are wholly independent from the properties of the units that compose it. Vitalism and mind-body dualism were strong forms of emergentism: life and mind were thought to possess characteristics that do not derive from the properties of inanimate molecules. Physicalism maintains that all phenomena -- including living systems -- depend ultimately upon physical entities and structures, so strong emergentism is rejected. But physicalism does not entail reductionism, so it is scientifically acceptable to provide explanations that presuppose relative explanatory autonomy.

Once we have reason to accept something like the idea of relative explanatory autonomy in the social sciences, we also have a strong basis for rejecting the exclusive validity of one particular approach to social explanation, the reductionist approach associated with methodological individualism and Coleman's boat. Rather, social scientists can legitimately aggregate explanations that call upon meso-level causal linkages without needing to reduce these to derivations from facts about individuals. And this implies the legitimacy of a fairly broad conception of methodological pluralism in the social science, constrained always by the requirement of microfoundations.

Issues about microfoundations

I believe that hypotheses, theories, and explanations in the social sciences need to be subject to the requirement of microfoundationalism. This requirement can be understood in a weak and a strong version, and sometimes people understand the idea as a requirement of reductionism.  In brief, I defend the position in a weak form that does not imply a reductionist theory of social explanation. Recent discussions with Julie Zahle have led me to sharpen my understanding of the requirement of microfoundations in social theorizing and explanation. Here I would like to clarify my own thinking about the role and scope of the principle of microfoundationalism.

A microfoundation is something like this: an account of the mechanisms at the individual actor level (and perhaps at levels intermediate between actors and the current level -- e.g. institutions) that work to create the structural and causal properties that we observe at the meso or macro level. A fully specified microfoundational account of a meso-level feature consists of an account that traces out (1) the features of the actors and (2) the characteristics of the action environment (including norms and institutions) which jointly lead to (3) the social pattern or causal power we are interested in. A microfoundation specifies the individual-level mechanisms that lead to the macro- or meso-level social fact. This is the kind of account that Thomas Schelling illustrates so well in Micromotives and Macrobehavior.

My thinking about the need for microfoundations has changed over the years from a more narrow requirement ("we need to have a pretty good idea of what the individual-level mechanisms are for a macro-property") to a less restrictive requirement ("we need to have reason to believe that there are individual-level mechanisms for a macro-property"). In The Scientific Marx I liked the idea of “aggregative explanations”, which are really explanations that move from features of individual actors and their interactions, to derivations about social and collective behavior. In Varieties of Social ExplanationI relaxed the idea along these lines:

This doctrine [of microfoundationalism] may be put in both a weak and a strong version. Weakly social explanations must be compatible with the existence of microfoundations of the postulated social regularities, which may, however, be entirely unknown. More strongly social explanations must be explicitly grounded on an account of the microfoundations that produce them. I will argue for an intermediate form—that we must have at least an approximate idea of the underlying mechanisms at the individual level if we are to have a credible hypothesis about explanatory social regularities at all, A putative explanation couched in terms of high-level social factors whose underlying individual-level mechanisms are entirely unknown is no explanation at all. (kl 4746)

My adherence to microfoundationalism today is a little bit weaker still. I now advocate a version of microfoundationalism that specifies only that we must be confident (an epistemic concept) that such micro-to-macro relations exist. We must be confident there are such mechanisms but not obliged to specify them. (I also hold that the best ground for having that confidence is being able to gesture plausibly towards roughly how they might work.) Another way to put it is this requirement: "No magical thinking!" That is, we exclude explanations that would only be possible if we assumed action at a distance, blocks of wood that have complicated mental lives, or intelligent beings with infinite computational faculties. A convincing way of discrediting a meso-level assertion is to give an argument that it is unlikely that real human agents would in fact act in ways that lead to this meso-level situation. (Example: Chinese planners who created the collective farming system in the Great Leap Forward assumed that collective farms would be highly productive because a "new socialist man" would emerge. This was unlikely, and therefore the individual behavior to be expected on collective farms would lead to "easy riding" and low productivity.)

Here is an effort to simplify these issues into a series of assertions:

1. All social forces, powers, structures, processes, and laws (social features) are ultimately constituted by mechanisms at the level of individual actors. (ontological principle)
2. When we assert the reality or causal powers of a social entity, we need to be confident that there are microfoundations that cause this social entity to have the properties we attribute to it. (microfoundations principle)
   1. A description of the microfoundations of a social entity S is an account of the circumstances and individual mechanisms that bring about patterns of individual activity resulting in the properties of S.
   2. Strong version: we must provide a credible statement of the microfoundations.
   3. Intermediate version: we must have a back-of-envelope sketch of possible microfoundations.
   4. Weak version: we must have confidence that there are microfoundations, but we don’t have to have any specific ideas about what they are.
3. A "vertical" social explanation of the features of a social entity S is a derivation of S from facts about the individual level. This is equivalent to providing a specification of the microfoundations of S; a derivation of the properties of S from a model of the action situation of the individuals involved; an agent-based model. This is what JZ calls an individualist explanation.
4. A "horizontal" social explanation is one in which we explain a social entity or structure S by referring to the causal properties of other meso-level entities and conditions. This is what we call a meso-level explanation. (The diagram above illustrates these ideas.)
   1. Horizontal explanations are likewise subject to the microfoundations requirement 2: the entities and powers postulated need to be such that we have good reason to believe that there are microfoundations available for these entities and properties. (Epistemic requirement)
   2. Or slightly stronger: we need to be able to offer at least a plausible sketch of the microfoundations / individual-level mechanisms that would support the postulated entities. (Epistemic+ requirement)
5. Providing or hypothesizing about microfoundations always involves modeling the behaviors and interactions of individuals; so it requires assuming a theory of the actor. So when we try to specify or hypothesize about microfoundations for something we are obliged to make use of some theory of the actor.
6. Traditional theories of the actor are generally too abstract and too committed to a rational-choice model.
7. Social scientists will be better able to hypothesize microfoundations when they have richer theories of the actor. (heuristic principle)

So the ontological principle is simply that social entities are wholly fixed by the properties and dynamics of the actions of the actors that constitute them. The requirement of microfoundations simply reproduces the ontological principle, ruling out ontologically impossible relations among social entities. The requirement of microfoundations is not a requirement on what an explanation needs to look like; rather, it is a requirement about certain beliefs we need to be justified in accepting when we advance a claim about social entities. It is what JZ calls a “confirmation” requirement (or perhaps better, a justificatory requirement). A better theory of the actor supports the discovery of microfoundations for social assertions. Further, it provides a richer "sociological imagination" for macro- and meso-level sociologists. So the requirement of microfoundations and the recommendation that social scientists seek out better theories of the actor are also valuable as heuristics for social research: they provide intellectual resources that help social researchers decide where to look for explanatory links, and what kinds of mechanisms might turn out to be relevant.

Social mechanisms and ABM methods

One particularly appealing aspect of agent-based models is the role they can play in demonstrating the inner workings of a major class of social mechanisms, the group we might refer to as mechanisms of aggregation. An ABM is designed to work out how a field of actors of a certain description, in specified kinds of interaction, lead through time to a certain kind of aggregate effect. This class of mechanisms corresponds to the upward strut of Coleman's boat. This is certainly a causal story; it is a generative answer to the question, how does it work?

However, anyone who thinks carefully about causation will realize that there are causal sequences that occur only once. Consider this scenario: X occurs, conditions Ci take place in a chronological sequence, and Y is the result. So X caused Y through the causal steps instigated by Ci. We wouldn't want to say the complex of interactions and causal links associated with the progress of the system through Ci as a mechanism linking X to Y; rather, this ensemble is the particular (in this case unique) causal pathway from X to Y. But when we think about mechanisms, we generally have in mind the idea of "recurring causal linkages", not simply a true story about how X caused Y in these particular circumstances. In other words, for a causal story to represent a mechanism, it needs to be a story that can be found to hold in an indefinite number of cases. Mechanisms are recurring complexes of causal sequences.

An agent-based model serves to demonstrate how a set of actors give rise to a certain aggregate outcome. This is plainly a species of causal argument. But it is possible to apply ABM methods to circumstances that are unique and singular. This kind of ABM model lacks an important feature generally included in the definition of a mechanism-- the idea of recurrence across a number of cases. So we might single out for special attention those ABMs that identify and analyze processes that recur across multiple social settings. Here we might refer, for example, to the "Schelling mechanism" of residential segregation. There are certainly other unrelated mechanisms associated with urban segregation -- mortgage lending practices or real estate steering practices, for example. But the Schelling mechanism is one contributing factor in a range of empirical and historical cases. And it is a factor that works through the local preferences of individual actors.

So this seems to answer one important question: in what ways can ABM simulations be said to describe social mechanisms? They do so when (i) they describe an aggregative process through which a given meso-level outcome arises, and (ii) the sequence they describe can be said to recur in multiple instances of social process.

A question that naturally arises here is whether there are social mechanisms that fall outside this group. Are there social mechanisms that could not be represented by an ABM model? Or would we want to say that mechanisms are necessarily aggregative, so all mechanisms should be amenable to representation by an ABM?

This is a complicated question. One possible response seems easily refuted: there are mechanisms that work from meso level (organizations) to macro level (rise of fascism) that do not invoke the features of individual actors. Therefore there are mechanisms that do not conform strictly to the requirements of methodological individualism. However, there is nothing in the ABM methodology that requires that the actors should be biological individuals. Certainly it is possible to design an ABM representing the results of competition among firms with different behavioral characteristics. This example still involves an aggregative construction, a generation of the macro behavior on the basis of careful specification of the behavioral characteristics of the units.

Another possible candidate for mechanisms not amenable to ABM analysis might include the use of network analysis to incorporate knowledge-diffusion characteristics into analysis of civil unrest and other kinds of social change. It is sometimes argued that there are structural features of networks that are independent of actor characteristics and choices. But given that ABM theorists often incorporate aspects of network theory into their formal representations of a social process, it is hard to maintain that facts about networks cannot be incorporated into ABM methods.

Another candidate is what Chuck Tilly and pragmatist sociologists (Gross, Abbott, Joas) refer to as the "relational characteristics" of a social situation. Abbott puts the point this way: often a social outcome isn't the result of an ensemble of individuals making discrete choices, but rather is a dance of interaction in which each individual's moves both inform and self-inform later stages of the interaction. This line of thought seems effective as a rebuttal to methodological individualism, or perhaps even analytical sociology, but I don't think it demonstrates a limitation of the applicability of ABM modeling. ABM methods are agnostic about the nature of the actors and their interactions. So it is fully possible for an ABM theorist to attempt to produce a representation of the iterative process just described; or to begin the analysis with an abstraction of the resultant behavioral characteristics found in the group.

I've argued here that it is legitimate to postulate meso-to-meso causal mechanisms. Meso-level things can have causal powers that allow them to play a role in causal stories about social outcomes. I continue to believe that is so. But considerations brought forward here make me think that even in cases where a theorist singles out a meso-meso causal mechanism, he or she is still offering some variety of disaggregative analysis of the item to be explained. It seems that providing a mechanism is always a process of delving below the level of the explananda to uncover the underlying processes and causal powers that bring it about.

So the considerations raised here seem to lead to a strong conclusion -- that all social mechanisms can be represented within the framework of an ABM (stipulating that ABM methods are agnostic about the kinds of agents they postulate). Agent-based models are to social processes as molecular biology is to the workings of the cell.

In fact, we might say that ABM methods simply provide a syntax for constructing social explanations: to explain a phenomenon, identify some of the constituents of the phenomenon, arrive at specifications of the properties of those constituents, and demonstrate how the behavior of the constituents aggregates to the phenomenon in question.

(It needs to be recognized that identifying agent-based social mechanisms isn't the sole use of ABM models, of course. Other uses include prediction of the future behavior of a complex system, "what if" experimentation, and data-informed explanations of complex social outcomes. But these methods certainly constitute a particularly clear and rigorous way of specifying the mechanism that underlies some kinds of social processes.)

Mechanisms and intellectual movements

I am particularly interested in the idea that we can explain social outcomes by identifying the social mechanisms that (often, typically, occasionally) bring them about. I also find the evolution of science and systems of ideas to be particularly fascinating within contemporary sociology, in that this aspect of human life embraces both rationally directed thought and sociological influences. So it is very interesting to consider what we can discover about the structures, networks, and professional organizations that influence the course that a given discipline or field of research takes.

It is therefore interesting to consider the role that reference to social mechanisms has played in recent works of the sociology of science and the sociology of knowledge. A particularly good example is found in the work of sociologists like Camic, Lamont, Gross, and Frickel, and Frickel and Gross's "General Theory of Scientific/Intellectual Movements" (2005) is a good place to start (link). Frickel and Gross put their goal in this article in this way:

The theory seeks to answer the question, under what social conditions is any particular scientific/intellectual movement, or SIM (whose nature we clarify shortly), most likely to emerge, gain adherents, win intellectual prestige, and ultimately acquire some level of institutional stability? (205)

This description evokes an explanatory goal with a causal perspective -- "conditions" that make "emergence" likely. But on its face this is not a mechanisms-based approach -- rather, it is more akin to a "facilitating or necessary conditions" kind of analysis of social causation. This impression is reinforced by the assertion that the theory is inductive, based on an examination of a number of case studies of SIMs aimed at identifying such conditions. (The authors also make a point of giving emphasis to failed SIMs because of the traction offered by such cases for counterfactual analysis.) They emphasize the importance of identifying common features of SIMs, in order to "mark them as objects for sociological study" (208), which implies that a precondition of sociological study is that we need to identify a social kind of entities with reasonably similar properties. This too suggests an underlying causal perspective that looks to regularities and common properties rather than causal mechanisms or causal powers.

As much of the recent discussion of critical realism makes clear, it is very important to be as explicit as possible about the assumptions we make about causation in the social sciences. So a quick review of the article may be useful in order to shed light on the kinds of causal thinking that Frickel and Gross engage in here.

To begin, what is a SIM?

The most abbreviated definition is this: SIMs are collective efforts to pursue research programs or projects for thought in the face of resistance from others in the scientific or intellectual community. (206)

So one criterion for an ensemble of thinkers and institutions to constitute a SIM in the F/G definition is that their shared intellectual program needs to challenge the status quo, the dominant way of thinking about the subject matter of concern. F/G explicitly model their analysis on the study of social movements; notice the parallel with McAdam, Tarrow, and Tilly's formulation in Dynamics of Contention of their central question.

Under what conditions will normally apathetic, frightened, or disorganized people explode into the streets, put down their tools, or mount the barricades? How do different actors and identities appear and transform in episodes of contention? Finally, what kinds of trajectories do these processes follow? (chapter 2)

It is interesting that F/G are quite explicit in looking for a "general theory". What they mean by this, apparently, is an account of a limited set of social conditions whose presence or absence "explains" the success or failure of a candidate SIM at a point in time. And this in turn sounds quite a bit like the comparative method pursued by Theda Skocpol in States and Social Revolutions: A Comparative Analysis of France, Russia and China: through comparative study of cases, discover a background set of social and political conditions that serve as jointly sufficient and/or necessary conditions for the occurrence of social revolution (link). (Like Skocpol, F/G make use of the probabilistic versions of sufficiency and necessity: "makes more likely" and "makes more unlikely".) Mechanisms come into the story fairly quickly: "Our general theory insists that the precise mechanisms whereby a field's external environment shapes a SIM must be specified" (209); but in fact, there is very little discussion of concrete mechanisms in the article.

The four premises of the general theory are these:

• Proposition 1: A SIM is more likely to emerge when high-status intellectual actors harbor complaints against what they understand to be the central intellectual tendencies of the day. (209; italics mine)
• Proposition 2: SIMs are more likely to be successful when structural conditions provide access to key resources. (213)
• Proposition 3: The greater a SIM's access to various micro mobilization contexts, the more likely it is to be successful. (219)
• Proposition 4: The success of a SIM is contingent upon the work done by movement participants to frame movement ideas in ways that resonate with the concerns of those who inhabit an intellectual field or fields. (221)

For each of these theoretical propositions they offer the sketch of an idea about what the mechanisms are that might support this factor. For example, concerning proposition 1, they maintain that "grievance" is a necessary condition for the emergence of an SIM because it puts potential adherents in a state of psychological readiness for mobilization. Another mechanism they cite for the emergence and mobilization of an SIM is the sudden entry into a field of non-traditional practitioners -- for example, women or African-American scholars entering the field of urban studies in the 1960s who found that prevailing wisdom failed to do justice to their own experiences. And on the resources point, F/G refer to the job market, academic organizations, and funding sources, and sketch out how favorable conditions with regard to these structural features can facilitate the success of a SIM. This is, at least in sketch, a mechanisms analysis.

The mechanisms associated with Proposition 3 are encapsulated in the notion of "micromobilization". Like Tilly in his analysis of the counter-revolution in The Vendee, F/G hold that the success of a SIM is influenced by the strength or weakness of the various organizations and networks through which it is able to spread its message and its mobilization efforts at the grassroots level. They mention laboratories, conferences, research retreats, and academic departments (219). Once one or more advocates of the given SIM has a position of influence in one of these centers, he or she is enabled to influence and mobilize other scholars to the SIM.

The mechanisms associated with Proposition 4 pick up on the rhetorical side of intellectual work.  We might unsympathetically refer to this aspect of the development of a SIM as the marketing campaign it pursues. In order to influence prospective adherents to an intellectual movement it is necessary to provide "messages" that resonate with them. (Fritz Ringer's analysis of the German mandarins between the wars in The Decline of the German Mandarins: The German Academic Community, 1890-1933 seems to illustrate this mechanism; a few highly effective reactionary authors caught the wave of pessimism that was present in German culture between the wars, and this seems to have had an important effect on the development of social science thinking in the period.) This factor has to do with effective framing of issues and research questions:

Fundamental to framing, and underlying and connecting to the three other dimensions we describe shortly, is the notion of intellectual identity. We see intellectual identity as one of the crucial links between micro, mess, and macro levels of analysis in the sociology of ideas. (222)

It is possible to take issue with the notion that there is a general theory on offer here. I would rather call the analysis provided here an account of some generalizations about the causal conditions that facilitate or impede intellectual movements. The phrase "general theory" makes the effort seem more comprehensive than it actually aims to be. What this treatment lacks (by design) is a micro- or meso-level account of how specific institutions, identity features, resource sources, and networks have played out in specific instances of intellectual change. (The contributions to Camic, Gross, and Lamont's Social Knowledge in the Making do this in a variety of ways.)

But consider Chuck Tilly's frequent critique of a similar effort in contentious politics studies: it is the underlying mechanisms and processes, not the general similarities and common conditions, that provide real insight into the explanation of episodes of contentious action. Tilly argues that there is a great deal of variation across episodes; but we can nonetheless discover some common underlying mechanisms and processes. And this would suggest that a more meso-level might be helpful in the study of SIMs as well. Or putting it in other terms, more attention to mechanisms and less emphasis on general conditions might provide more insight into the phenomena of intellectual movements.

There is one final observation that appears relevant here. The "social mechanisms" approach itself might be classified as a SIM in the making. This intellectual movement involves a relatively small group of practitioners embedded within specific centers of institutional influence; it emerged from dissatisfaction with the received view of causation in the social sciences; and it is involved in a struggle for resources and prestige in the field of the philosophy of social science, both in Europe and North America. (For that matter, much the same could be said for critical realism.)

Finally, I am keeping my eyes open for meso-level social mechanisms in the sociology literature, and so I was curious in reading through this piece again whether any of the mechanisms postulated here were meso-meso. It seems that they are not. Rather, the social mechanisms mentioned generally proceed from a structure or institution to individual behavior (meso-micro) or from individual behavior to a meso- or macro-level outcome (progress of the SIM). But if this is correct, then the explanatory work offered here conforms to the downward and upward struts of Coleman's boat, not the type 4 causation from meso to meso that Coleman precludes (link). This makes the analysis perhaps more compatible with the strictures of analytical sociology that the authors might have guessed (link).

Doug McAdam on contentious politics and the social sciences

Doug McAdam is hard at work shedding new light on the meso-dynamics of contention.  What are the specific social and psychological mechanisms that bring people into social movements; what factors and processes make mobilization more feasible when social grievances arise?  Recently he has done work on the impact of Teach for America on its participants, and he and his graduate students are now examining a set of environmental episodes that might have created local NIMBY movements -- but often didn't.

McAdam's most sustained contribution to the field of contention is his 1982 book on the dynamics of the struggle for racial equality, Political Process and the Development of Black Insurgency, 1930-1970.  The book was reissued in 1999 with a substantive new introduction, and it has set the standard for sophisticated sociological study of a large, complex movement.  McAdam collaborated with Sidney Tarrow and Chuck Tilly in articulating a new vision of how to approach the politics of contention in Dynamics of Contention.  And he has co-authored or co-edited another half dozen books on social movements and popular mobilization.  So McAdam has been one of the architects of the field of contentious politics.  Most importantly, he and his collaborators have brought innovative new thinking to the definition of problems for social research.

So it is valuable to dig into some of McAdam's thoughts and his sociological imagination as we think about how the sociology of the future might be shaped.  I conducted an extensive interview with Doug earlier this month, and it opened up quite a few interesting topics.  The full interview is posted on YouTube (link).



There are quite a few important turns to the conversation.

1. Segment 1: Why is the study of contention a central topic within the social sciences?
2. Segment 2: How can we approach contention without looking only at the successful cases?  How about the moments where contention might have developed but did not?  We can combine quantitative and qualitative methods -- perhaps in an order that reverses the usual approach.  Maybe we can use quantitative studies to get a general feel for a topic, and then turn to qualitative and case studies to discover the mechanisms.
3. Segment 3: Another important theme: "We are voracious meaning-making creatures." Human beings have a cognitive-emotional-representational ability to attempt to represent meanings and their own significance within the larger order.  Rational choice theory has too narrow a conception of agency.  Why did the Black community stay off the buses in Montgomery?  Because people were strongly enmeshed in communities of meaning and commitment that framed the bus boycott in terms of meaning and identity.
4. Segment 4: The psychology of mobilization is complex.  It's not just "rational incentives".  Organizers and leaders use the affinities and loyalties of the community to bring about collective action.  For example, an interesting strategy by SNCC to "shame" church leaders into supporting activists.  Movements happen very suddenly; this seems to reflect a process of "redefining" the situation for participants.  Another interesting issue: what is the right level of analysis -- micro, meso, or macro?  Doug favors the "meso" level.
5. Segment 5: More on the meso level: disaggregated social activity.  McAdam argues that government actions are themselves often at the meso level.  And he makes the point that Civil Rights reform was strongly influenced in the United States by the issues created internationally through the tensions and ideological conflicts of the Cold War.  This explains why it was Truman rather than Roosevelt who endorsed the need for Civil Rights reform.  You can't explain the broad currents of the Civil Rights movement without understanding the international context that was influencing the Federal government.  (This is an example of a macro-level effect on social movements.)
6. Segment 6: Now to mechanisms and processes.  There are no laws of civil wars.  So we need to look downward into the unfolding of the episodes of contention.  Comparative historical sociology is a very dynamic movement today.  Your work isn't quite as comparative as that of Tilly or McAdam.  Doug indicates that he favors comparison; but he tends to choose cases that are broadly comparable with each other.  Tilly often made comparisons at a much higher level of variation.  Q: Would you have been comfortable framing your study of the American Civil Rights movement as a comparison with the Solidarity Movement in Poland?  A: no.  There is too broad a range of differences between the cases.
7. Segment 7: McAdam offers some interesting observations about the relationship between general theory and the specific social phenomena under study.  An important point here is a strong advocacy for eclectic, broad reading as one approaches a complex social phenomenon.  We can't say in advance where the important insights are going to come from -- anthropology, political science, history, sociology, ....
8. Segment 8: We can dig into the social features that make certain figures very successful in bringing a group of people into a readiness to engage together.  Is social status a key factor?  Is it that some people are particularly persuasive?  Doug wants to break open the black box and get a lot better understanding of the meso-level processes and mechanisms through which mobilization occurs.  A closing topic: what about protest and mobilization in Asia?  Do you think these ideas about mobilization are relevant and illuminating in China or Thailand?  Or has it developed in too specific a relationship to democratic societies? Does the current understanding of popular mobilization help us when we try to understand movements like the Redshirt movement in Thailand?  Doug believes the framework is relevant outside the democratic West.  The ideas need to be applied loosely and flexibly.
9. Segment 9: So the theory is really a "sketch" of the space of mobilization, rather than a set of specific hypotheses about how mobilizations always work.  And in that understanding -- the field is very relevant to research on the Thailand movement.

(Note the strong connections between this discussion and a few of the earlier interviews -- Tilly, Tarrow, and Zald in particular (link).  My interview with Gloria House about her experience with SNCC in Lowndes County is very relevant as well (link).)