Methodological localism and actor-centered sociology

I've advocated in earlier posts for two related ideas: the idea of actor-centered sociology and the idea of methodological localism. The first idea recommends that sociologists couch their research and theories in terms of more specific and nuanced theories of the actors whose thoughts and actions make up the social processes of interest. The second idea is an alternative to the equally unappealing doctrines of methodological individualism and holism. According to methodological localism, the "molecule" of the social world is the socially constituted, socially situated actor in ongoing relationships with other social actors. This is a conception of social reality that is social all the way down; it conceives of the individual actor within a set of social relationships as the basic unit of social phenomena.

Examination of some important work in sociology and neighboring fields in the past several decades shows that the actor-centered approach corresponds pretty well to the research approach taken by a number of innovative investigators. Here are a few examples: C. K. Lee, Against the Law: Labor Protests in China's Rustbelt and Sunbelt; Michael Mann, The Dark Side of Democracy: Explaining Ethnic Cleansing; George Steinmetz, The Devil's Handwriting: Precoloniality and the German Colonial State in Qingdao, Samoa, and Southwest Africa; Al Young, The Minds of Marginalized Black Men: Making Sense of Mobility, Opportunity, and Future Life Chances; Elinor Ostrom, Governing the Commons: The Evolution of Institutions for Collective Action. Each of these research projects makes significant use of more nuanced theories of the actor as an important part of the analysis and explanations offered.

These examples validate the usefulness of several of the key imperatives of the doctrine of methodological localism: in particular, emphasis on the centrality of the socially situated and socially constructed actor within more complex social processes. Methodological localism implies that we need to be cautious about over-simplifying the mentality of the actor—not simply a utility maximizing egoist, not simply a norm-driven robot, not simply an adherent of a religious worldview.

Instead, it is often useful to pay attention to the details and the differences that we find in the historical setting of important social processes and outcomes and the forms of mentality these create: the specific forms of education received by scientists, the specific social environment in which prospective administrators were socialized, the specific mental frameworks associated with this or that historically situated community. These details help us to do a much better job of understanding how the actors perceived social situations and how they chose to act within them.

And likewise, it is often useful to pay attention to the regulative and incentive-generating context within which actors constructed their actions. This is the role that the intellectual and policy field plays in Steinmetz’s account; it is also the role that specific property and contract arrangements play in the new institutionalism and Elinor Ostrom. And both Bourdieu and the new institutionalists are right that small differences in the institutional setting can result in large differences in outcome, as actors respond to institutions and incentives to pursue their ends. So paying close and detailed attention to the particulars of the institutions of career, economic opportunity, family, power, and prestige allows us to perceive the causes of important differences in outcomes.

In short, it seems that sociology has a lot to gain by paying more attention to the specifics of the actors whose thinking and actions constitute the social processes of interest to them. This advice does not imply reductionism; it is entirely legitimate for sociologists to make use of causal claims at a variety of levels. But it does imply that there is substantive and valuable work to be done in almost every field of sociology at the level of the actor. Sociology gains when researchers attempt to gain a more nuanced understanding of the constitutions and situations of the actors with whom they are concerned.

To be sure, not all research in sociology takes this approach. And in fact there is very good recent work in sociology that doesn't pay much attention to the actor. A good example of this category is Robert Sampson's Great American City: Chicago and the Enduring Neighborhood Effect.  Sampson's approach has everything to do with the behavior of particular actors in particular circumstances. He wants to show that we can identify certain patterns of causation that exist in urban street-scapes that are amenable to quantitative investigation.  But his research is not particularly socio-ethnographic; no interviews, no attempt to capture the states of mentality of the urban young people who make up the neighborhoods he studies.  The level of analysis that he has chosen is largely higher than the individual actors -- the meso-level environmental and organizational features that appear to have an effect on collective behavior. And one of his main methodological contributions is to oppose the idea that urban phenomena can be derived from facts about the individuals who make up a neighborhood or city. So Sampson's research and explanations are evidently not "actor-centered." But I think that Sampson's work is compatible nonetheless with the thesis of methodological localism, though this is less clear. Sampson insists that the neighborhood-level characteristics have causal consequences that do not disaggregate into individual-level patterns. But this can be understood in the "relative explanatory autonomy" interpretation offered elsewhere (link): microfoundations exist for these effects, but it isn't necessary to trace them through in order to validate the causal linkage at the neighborhood level.

These observations suggest that the status of these two big ideas is rather different. The idea of "actor-centered" sociology shouldn't be understood as a general prescription for all sociological research, but rather as simply a promising line of investigation as we try to shed light on various social processes and outcomes.  The idea of methodological localism, on the other hand, is a fairly general ontological claim about what the social world is made up of, and it is intended as a general premise for how we think about all social phenomena.  It doesn't entail a particular theory of explanation, but it does provide a general account of the constitution of social phenomena. And it has implications for how we should think about the micro-composition of social causation.

 

Simon on complexity

Herbert Simon's The Sciences of the Artificial - 3rd Edition provided an alternative model for thinking about society. We can think of social institutions as partially designed and selected for their organizational properties; so they are different from proteins and planetary systems.  Simon is also an important contributor to the study of complexity. So his new chapter in the 1996 edition of the book, "Alternative Views of Complexity," is worth reading carefully. Here is how he motivates this new chapter in SA:

The preceding chapters of this book have discussed several kinds of artificial systems. The examples we have examined -- in particular, economic systems, the business firm, the human mind, sophisticated engineering designs, and social plans -- range from the moderately to the exceedingly complex (not necessarily in the order in which I have just listed them). These final two chapters address the topic of complexity more generally, to see what light it casts on the structure and operation of these and other large systems that are prominent in our world today. (169)

It turns out that there isn't much new in the 1996 chapter, however. In fact, most of its content is taken from his pathbreaking 1962 article, "The Architecture of Complexity" (link). The new chapter 7 and renumbered chapter 8 largely incorporate the content and sometimes the language of the 1962 article. And this is interesting, because it implies that Simon's primary ideas about reduction, composition, and inter-level interactions were largely already formed in 1962.

 

There are a few ideas and themes that are new to the 1996 version. One is a more specific periodization of thinking about complexity theory in the twentieth century.  The 1996 version identifies three phases of theorizing about complexity and "whole systems".

1. Biological emergence theory (post World War I)
2. Cybernetics and systems theory (post World War II)
3. Contemporary complexity theory (post 1960s)

Simon is skeptical about the tendency towards irreducible holism that was associated with the earlier two phases of thinking in both versions; in the 1996 chapter he favors a "weak" interpretation of emergence: a commitment to ...

... reductionism in principle even though it is not easy (often not even computationally feasible) to infer rigorously the properties of the whole from knowledge of the properties of the parts. In this pragmatic way, we can build nearly independent theories for each successive level of complexity, but at the same time, build bridging theories that show how each higher level can be accounted for in terms of the elements and relations of the next level down. (172)

This "pragmatic holism" is already contained in the 1962 version (link). So this doesn't represent new ground in 1996. But Simon's use of this idea to criticize several false starts in the field of complexity research is valuable.

Simon finds some of the central concepts of the third phase to be more promising for the study of social phenomena. The mathematics and physics of chaotic behavior (where simple low-level processes can aggregate to wildly variant higher-level outcomes), simulations of evolution through computational models (genetic algorithms), and the exploration of cellular autonoma (the game of life) all come in for favorable comments. (The Lorenz attractor illustrated here is a common example of chaotic behavior.)

One idea that is not contained in the 1962 version is that of causal non-linearity. Non-linearity is a problem for the "near decomposability" view that Simon wanted to take of complexity in the 1962 version, because it casts doubt on the ability to disentangle causal influences deriving from inter-connected subsystems. Small differences in initial conditions can lead to large differences in outcome. This is a key aspect of chaos theory and the varieties of turbulent phenomena that provide the best examples of chaotic systems. And this casts some doubt on one of the central conclusions of the 1962 paper:

The fact, then, that many complex systems have a nearly decomposable, hierarchic structure is a major facilitating factor enabling us to understand, to describe, and event to "see" such systems and their parts. Or perhaps the proposition should be put the other way round. If there are important systems in the world that are complex without being hierarchic, they may to a considerable extent escape our observation and our understanding. (477)

This is a decidedly pre-chaos understanding of the nature of complex systems. I have the impression that many contemporary complexity theorists would reject the idea that social processes are commonly the result of "nearly decomposable, hierarchic structures". So it is a genuine change for the mathematics of chaos theory to be included in the 1996 version. Complexity research has moved forward since 1962, and Simon recognizes this in the 1996 chapter.

What we don't find here is any discussion of whether actual social processes and systems display chaotic behavior in this well defined sense. And we don't see Simon shifting his position on "nearly decomposable" systems.

Are there examples of social processes and phenomena that display chaotic characteristics over time? Take the occurrence of massive street demonstrations as an example; are there aspects of chaos in the technical sense involved in the outbreak of street mobilization? Do small, apparently random events have large effects on the eventual outcome?

It would appear that this is the case when we look at the cases of uprising and passivity in different cities during the Arab Spring of 2011. Some social scientists have tried to understand the likelihood of uprising as an increasing function of economic crisis, regime weakness, and regime brutality. This implies a linear assumption about the causal role of these three forces. But it seems plausible to speculate that random events like a broken phone chain, an Internet outage, or the defection of a key leader could push the process of mobilization into a different direction. Moreover, it seems that contemporary research on social complexity pays a lot of attention to non-linearity, path-dependency, and sequential processes of social mobilization -- leaving a lot of room for the kinds of turbulent effects that are observed in traffic flow, storm generation, and water dripping from a leaking tap. This is the kind of work that is described in Scott Page and John Miller, Complex Adaptive Systems: An Introduction to Computational Models of Social Life.

So oddly enough, it seems that one could fairly say that Simon's views of social complexity -- as expressed in the 1996 third edition of  The Sciences of the Artificial as well as in his groundbreaking "Architecture of Complexity" in 1962 -- are significantly incomplete, given the way that complexity theorists are now thinking about social processes. Simon did not incorporate the guiding assumptions of "complex adaptive systems theory" into his own thinking, and remained convinced of the adequacy of the ideas of hierarchical systems and nearly decomposable systems as late at 1996.  His own approach to social complexity remains a phase two approach, not a phase three approach.

(The graph at the top of this post is offered as an interpretation of a highly path-dependent social process. The reader is asked to consider each path as a hypothetical development from a common origin, with small stochastic variations in the situation occurring over time. Imagine the starting position is "large city, economic hardship, weak state, lots of repression", time is the x axis, and the y axis measures civil unrest. Some of those variations push the path towards a high outcome (blue), and some towards a low outcome (magenta). The great majority of outcomes fall within a short distance of the starting position. So the most likely outcome is "not much change", but there are unlikely but diametrically different outcomes possible as well.)

New metaphors for the social

The social world is not like the natural world. Nature is composed of things, forces, and geometries that have strong determining regularities whose interactions can be formulated with mathematical precision. There are problems of indeterminacy in physics, of course; but fundamentally we can rely on the material properties of steel, the magnetic properties of the sun, or the curvature of space-time to continue to work as expected. Nature constitutes a system of interactions. And this is because, fundamentally, nature consists of atoms and forces -- as some of the pre-Socratic philosophers thought 2,500 years ago.

The social world is different. It is not a system, but rather a patchwork, a mixture, an ensemble, a Rube Goldberg machine, a collage, or a jumble. Its properties arise from the activities, thoughts, motivations, emotions, and interactions of socially situated persons. Outcomes are influenced by a hodgepodge of obstacles and slopes that crop up more or less randomly -- leading to substantial deviations in the way we might have expected things to work out. Agents are not fully predictable or comprehensible; and their actions and interactions are indeterminate as well. We discover that people usually compare costs and benefits when they make choices, and we invent rational choice theory and microeconomics. But these are simply abstract models of one aspect of human behavior and choice, and it is rare indeed to find large social processes that are governed exclusively by this aspect of agency. We see large, somewhat stable social structures that persist over time -- patterns of habitation and social exchange (cities),  patterns of racial or ethnic discrimination, rising and falling rates of violent crime -- and we believe there are social causes and influences that help to explain these dynamic configurations. But we should never imagine that social outcomes and patterns are the manifestation of an underlying abstract social order, analogous to laws of nature. Social causes are heterogeneous, probabilistic, exception-laden, and inter-connected -- with the result that we can't hope to have a full model of the workings of a social system.

The heterogeneity and contingency associated with the social world suggested by this set of ideas do not imply that social scientific research and knowledge are unattainable. It implies, rather, that we need to understand the limits on representation, abstraction, and prediction that are implied by the fundamental nature of social things.  Our knowledge of any particular snapshot of social reality is inherently partial and incomplete.

A number of sociologists and philosophers have put their fingers on this important problem of social ontology. Here is Bruno Latour in Reassembling the Social: An Introduction to Actor-Network-Theory:

The argument of this book can be stated very simply: when social scientists add the adjective 'social' to some phenomenon, they designate a stabilized state of affairs, a bundle of ties that, later, may be mobilized to account for some other phenomenon. There is nothing wrong with this use of the word as long as it designates what is already assembled together, without making any superfluous assumption about the nature of what is assembled. (1)

Here is Norbert Elias in The Society of Individuals:

 Society is understood either as a mere accumulation, an additive and unstructured collection of many individual people, or as an object existing beyond individuals and incapable of further explanation. In this latter case the words available to us, the concepts which decisively influence the thought and action of people growing up within their sphere, make it appear as if the single human being, labelled the individual, and the plurality of people conceived as society, were two ontologically different entities. (vii)

What kind of formation is it, this "society" that we form together, which has not been intended or planned by any of us, or even all of us together? It only exists because a large number of people exist, it only continues to function because many individual people want and do certain things, yet its structure, its great historical transformations, clearly do not depend on the intentions of particular people. (3)

What we lack -- let us freely admit it -- are conceptual models and an overall vision by which we can make comprehensible in thought what we experience daily in reality, by which we could understand how a large number of individuals form with each other something that is more and other than a collection of separate individuals -- how they form a "society", and how it comes about that this society can change in specific ways, that it has a history which takes a course which has not been intended or planned by any of the individuals making it up. (7)

And now Manuel Delanda in A New Philosophy of Society: Assemblage Theory and Social Complexity:

Is there, for example, such a thing as society as a whole? Is the commitment to assert the existence of such an entity legitimate? And, is denying the reality of such an entity equivalent to a commitment to the existence of only individual persons and their families? The answer to all these questions is a definitive no, but several obstacles must be removed before justifying this negative response. Of all the obstacles standing in the way of an adequate social ontology none is as entrenched as the organismic metaphor. (8)

So we should not think of the social world in analogy with examples drawn from what we know about the natural world.  We should not think of society as a "thing" or a unified system. The ontological properties of the the natural and social realms are substantially different.  This is the primary reason I find some of the basic ideas of assemblage theory appealing: because these theories and theorists deliberately question the naturalistic approach to the social world, and they attempt to advance strikingly different and original concepts for characterizing the social world. They emphasize heterogeneity and composition over uniformity and subsumption.

It is striking to consider the parallel that emerges between this way of thinking about the "social" and some post-Cartesian ways of thinking about the "self". Some philosophers and psychoanalysts have argued that we should question the idea of the unified self that has governed the philosophy of mind since Descartes.  Instead, we should consider the notion that the self is not a unified center of consciousness and will, but rather a loose and contingent collage of psychological, physiological, and neurophysiological processes; that the impression of a unified self is a post-facto illusion; and that acting, thinking individuals are coalitions of a heterogeneous and often conflicting group of cognitive, emotional, and practical processes. These are radical challenges to the rationalist theory of the unified self. And they bear a striking similarity  to the assemblage challenge to the idea of society as a law-governed  structural-functional system.

Here is a word cloud of descriptors that seem accurate in application to the social world.

Readers -- what sociologists or philosophers do you think do a good job of characterizing the nature of the social world? What metaphors and concepts do you find most helpful in thinking about the social world?

Simulating social mechanisms

A key premise of complexity theory is that a population of units has "emergent" properties that result from the interactions of units with dynamic characteristics. Call these units "agents".  The "agent" part of the description refers to the fact that the elements (persons) are self-directed units.  Social ensembles are referred to as "complex adaptive systems" -- systems in which outcomes are the result of complex interactions among the units AND in which the units themselves modify their behavior as a result of prior history.

Scott Page's Complex Adaptive Systems: An Introduction to Computational Models of Social Life provides an excellent introduction. Here is how Page describes an adaptive social system:

Adaptive social systems are composed of interacting, thoughtful (but perhaps not brilliant) agents. It would be difficult to date the exact moment that such systems first arose on our planet -- perhaps it was when early single-celled organisms began to compete with one another for resources.... What it takes to move from an adaptive system to a complex adaptive system is an open question and one that can engender endless debate. At the most basic level, the field of complex systems challenges the notion that by perfectly understanding the behavior of each component part of a system we will then understand the system as a whole. (kl 151)

Herbert Simon added a new chapter on complexity to the third edition of The Sciences of the Artificial - 3rd Edition in 1996.

By adopting this weak interpretation of emergence, we can adhere (and I will adhere) to reductionism in principle even though it is not easy (often not even computationally feasible) to infer rigorously the properties of the whole from knowledge of the properties of the parts. In this pragmatic way, we can build nearly independent theories for each successive level of complexity, but at the same time, build bridging theories that show how each higher level can be accounted for in terms of the elements and relations of the next level down. (172).

This formulation amounts to the claim of what I referred earlier to as "relative explanatory autonomy"; link. It is a further articulation of Simon's view of "pragmatic holism" first expressed in 1962 (link).

So how would agent-based models (ABM) be applied to mechanical systems? Mechanisms are not intentional units. They are not "thoughtful", in Page's terms. In the most abstract version, a mechanism is an input-output relation, perhaps with governing conditions and with probabilistic outcomes -- perhaps something like this:

In this diagram A, B, and D are jointly sufficient for the working of the mechanism, and C is a "blocking condition" for the mechanism. When A,B,C,D are configured as represented the mechanism then does its work, leading with probability PROB to R and the rest of the time to S.
So how do we get complexity, emergence, or unpredictability out of a mechanical system consisting of a group of separate mechanisms? If mechanisms are determinate and exact, then it would seem that a mechanical system should not display "complexity" in Simon's sense; we should be able to compute the state of the system in the future given the starting conditions.

There seem to be several key factors that create indeterminacy or emergence within complex systems.

One is the fact of causal interdependency, where the state of one mechanism influences the state of another mechanism which is itself a precursor to the first mechanism.  This is the issue of feedback loops or "coupled" causal processes. Second is non-linearity: small differences in input conditions sometimes bring about large differences in outputs. Whenever an outcome is subject to a threshold effect, we will observe this feature; small changes short of the threshold make no change in the output, whereas small changes at the threshold bring about large changes. And third is the adaptability of the agent itself.  If the agent changes behavioral characteristics in response to earlier experience (through intention, evolution, or some other mechanism) then we can expect outcomes that surprise us, relative to similar earlier sequences. And in fact, mechanisms display features of each of these characteristics. They are generally probabilistic, they are often non-linear, they are sensitive to initial conditions, and at least sometimes they "evolve" over time.

So here is an interesting question: how do these considerations play into the topic of understanding social outcomes on the basis of an analysis of underlying social mechanisms? Assume we have a theory of organizations that involves a number of lesser institutional mechanisms that affect the behavior of the organization. Is it possible to develop an agent-based model of the organization in which the institutional mechanisms are the units? Are meso-level theories of organizations and institutions amenable to implementation within ABM simulation techniques?

Here is a Google Talk by Adrien Treuille on "Modeling and Control of Complex Dynamics".

The talk provides an interesting analysis of "crowd behavior" based on a new way of representing a crowd.

Neighborhood effects

 

In Great American City: Chicago and the Enduring Neighborhood Effect Robert Sampson provides a very different perspective on the "micro-macro" debate. He rejects the methodologies associated both poles of the debate: methodological individualism ("derive important social outcomes from the choices of rational individuals") and methodological structuralism ("derive important social outcomes from the features of large-scale structures like globalization"). Instead, he argues for the causal importance of a particular kind of "meso" -- the neighborhood. He takes the view that neither "bottom-up" or "top-down" sociology will suffice. Instead, we need to look at processes at the level of socially situated individuals.

In this book I proposed an alternative to these two perspectives by offering a unified framework on neighborhood effects, the larger social organization of urban life, and social causality in general…. Contrary to much received wisdom, the evidence presented in this book demands attention to life in the neighborhoods that shape it. (357)

I argue that we need to treat social context as an important unit of analysis in its own right.  This calls for new measurement strategies as well as a theoretical framework that do not treat the neighborhood simply as a "trait" of the individual. (60)

Sampson offers his own instantiation of Coleman's Boat to illustrate his thinking:

But unlike Coleman (and like the argument I offered in an earlier post about meso-level explanation; link), Sampson allows for the validity of type-4 causal mechanisms, from "neighborhood structure and culture" to "rates of social behavior". So neighborhoods are not simply outcomes of individual choices and behavior; they are social ensembles that exert their own causal powers.
Sampson offers an articulated methodology for the study of the social life of a city, in the form of ten principles. These include:

1. Focus on social context
2. Study contextual variations in their own right
3. focus on social-interactional, social psychological, organizational, and cultural mechanisms of social life
4. integrate a life-course focus on neighborhood change
5. look for processes and mechanisms that explain stability
6. embed in the study of neighborhood dynamics the role of individual selection decisions
7. go beyond the local
8. incorporate macro processes 
9. pay attention to human concerns with public affairs 
10. emphasize the integrative theme of theoretically interpretive empirical research while maintaining methodological pluralism (67-68)

The heart of "neighborhood sociology" can be summarized, Sampson asserts, in a few simple themes:

First, there is considerable social inequality between neighborhoods, especially in terms of socioeconomic position and racial/ethnic segregation.  

Second, these factors are connected in that concentrated disadvantage often coincides with the geographic isolation of racial minority and immigrant groups.  

Third, a number of crime- and health-related problems tend to come bundled together at the neighborhood level and are predicted by neighborhood characteristics such as the concentration of poverty, racial isolation, single-parent families, and to a lesser extent rates of residential and housing instability.  

Fourth, a number of social indicators at the upper end of what many would consider progress, such as affluence, computer literacy, and elite occupational attainment, are also clustered geographically. (46)

This set of themes asserts a series of important correlations between neighborhood features and social outcomes. The hard question is to identify the social mechanisms that underlie these correlations. "It is from this idea that in recent decades we have witnessed another turning point in the form of a renewed commitment to uncovering the social processes and mechanisms that account for neighborhood (or concentration) effects. Social mechanisms provide theoretically plausible accounts of how neighborhoods bring about change in a given phenomenon" (46).
This is a fascinating and methodologically innovative piece of urban sociology. Sampson's use of large data sets to establish some of the intriguing neighborhood patterns he identifies is highly proficient, and his efforts to place his reasoning within a more theoretically sophisticated framework of multi-level social mechanisms is admirable. In an interesting twist, Sampson shows how it is possible to expand on the very costly video-based methodology of the original PHDCN study by making use of Google Street View to do systematic observations of neighborhoods in Chicago and other cities (361).
(Here is an earlier post on Sampson's ideas about neighborhood effects.)

Assemblage theory

 

Deleuze's theory (metaphor?) of assemblage as a way of thinking about the social world is an intriguing one. Fundamentally the idea is that there does not exist a fixed and stable ontology for the social world that proceeds from "atoms" to "molecules" to "materials". Rather, social formations are assemblages of other complex configurations, and they in turn play roles in other, more extended configurations.

What is appealing to me about this way of talking about the social world is that it takes us away from the presuppositions we often bring about the social world as consisting of a range of discrete social objects or things. According to this static way of thinking, the state is a thing composed of other things; likewise Islam is an extended social thing; likewise Chicago; and so on. The assemblage approach suggests a different set of metaphors for the social world: mosaic, patchwork, heterogeneity, fluidity, transitory configuration. And this seems like a more realistic way of characterizing large extended social formation like states or regulatory agencies.

The downside of this way of talking and thinking about the social world is precisely the indefiniteness and indeterminacy it suggests for the composition relation. This poses a very hard problem for explanation. How are we to explain the properties and behavior of the composite entity if there is so much contingency in its parts and the ways in which they interact? The strategy of aggregative explanation seems to be a non-starter, since it is stipulated that composition is not a strongly rule-governed process. But so do the comparative and generalizing strategies. If the composites are indeed sui generis and unique configurations we can't generalize across instances and can't usefully compare them.

So how can we gain greater clarity? The concept of assemblage is expressed by Gilles Deleuze; but it is obscure. Here is a valuable blog post by Levi Bryant in LarvalSubjects that extracts several of Deleuze's statements about assemblage from an interview. This interview provides some description of the construct in Deleuze's own words.  Here is one of Bryant's efforts at clarifying Deleuze's meaning:

Assemblages are composed of heterogeneous elements or objects that enter into relations with one another. These objects are not all of the same type. Thus you have physical objects, happenings, events, and so on, but you also have signs, utterances, and so on. While there are assemblages that are composed entirely of bodies, there are no assemblages composed entirely of signs and utterances.

It isn't easy to paraphrase Deleuze's thinking into a more analytical formulation (though Bryant's efforts are helpful). But the language remains metaphorical, suggestive, and elusive, rather than analytical and discursive. For this reason it is difficult to determine whether the concept has value for sociological theory.

The core ideas are spelled out in a somewhat more accessible form in Manuel DeLanda's A New Philosophy of Society: Assemblage Theory and Social Complexity. DeLanda tries to explain "assemblage" by saying what it is not.  First, assemblage theory is opposed to essentialism and reification (26ff.). DeLanda emphasizes that Deleuze's concept resists the "organismic" approach to conceptualizing the social, by which he means an approach that looks at the whole as an inextricable combination of interrelated parts. This implies that the parts are implicated in each other; the organismic perspective emphasizes the internal connectedness of a thing. (This has affinity to Bert Ollman's philosophy of internal relations in Alienation: Marx's Conception of Man in a Capitalist Society.) DeLanda distinguishes between "interiority" and "exteriority" in conceptualizing the components of a thing. For assemblage theory, the relations among the parts are contingent, not necessary. And, crucially, parts can be extracted from one whole and inserted into another. "These relations imply, first of all, that a component part of an assemblage may be detached from it and plugged into a different assemblage in which its interactions are different. In other words, the exteriority of relations implies a certain autonomy for the terms they relate" (10-11). Another aspect of the theory, according to DeLanda, is the fact that it does not privilege one level of organization over another. "Micro" is not more fundamental than "macro"; instead, social reality is "multiscaled" (38), with assemblages occurring at every level.

Truthfully, neither Deleuze nor DeLanda succeeds in making the concept of assemblage a very clear or analytically specific one. So let's consider a diluted version of assemblage theory that might nonetheless be useful for sociological theory while foregoing much of the metaphysical language characteristic of Deleuze's writings:

1. Social entities are composed of components and lesser systems.
2. The components of a social entity are heterogeneous.
3. The components include both material factors and meaningful expressions.
4. The components have their own characteristics and dynamics.
5. The components may have very different temporal and spatial scales.
6. The effects and interactions among components may be indeterminate because of complexity effects and probabilistic causal mechanisms.
7. The behavior of the whole is difficult or impossible to calculate even given extensive knowledge of the dynamics of the components.

To illustrate this set of ideas, consider a city as an assemblage.

1. A city consists of population, businesses, roads, organizations, government policies, political movements, disaffected youth, and slogans.
2. Population dynamics have a temporal scale of decades, while businesses have a temporal scale of months.
3. The interaction effects of gradual population change, the voting system, and gradual environmental change are difficult to calculate.
4. We can nonetheless make efforts to disentangle the effects of population change, institutional design, and environment on things like land use and effective taxation rates.

This reformulation suggests that large social entities are "messy" but still amenable to analysis and study; and this is what sociology requires.

(Daniel Smith's article on Deleuze in the Stanford Encyclopedia of Philosophy is a readable exposition of Deleuze's philosophy; link. Another useful resource on assemblage theory is Nick Srnicek's masters' thesis; link. )

Methodological individualism today

Is it possible to draw a few conclusions on the topic of methodological individualism after dozens of years of debate? (Lars Udehn's Methodological Individualism: Background, History and Meaning is a great study of the long history of the debate over this issue. It is unfortunate there isn't an affordable digital edition of the book. Joseph Heath's entry on the subject in the Stanford Encyclopedia of Philosophy gives a very good overview; link.) Here is Jon Elster's formulation of the concept in Nuts and Bolts for the Social Sciences (1989):

The elementary unit of social life is the individual human action. To explain social institutions and social change is to show how they arise as the result of the actions and interaction of individuals. This view, often referred to as methodological individualism, is in my view trivially true. (13)

Max Weber is often identified as the modern originator of theory of methodological individualism. (Weber's student Joseph Schumpeter was the first to use the concept in print.) Weber's reason for advocating for MI derived from his view of action as purposive behavior, and his view that social outcomes need to be explained on the basis of the purposive actions of the individual actors who constitute them. So MI began with a presupposition about the unique importance of rational-intentional behavior in social life. Weber insisted on a rational actor foundation for the social sciences. And this prepared the ground for a joining of forces between methodological individualism and rational choice theory.

The emphasis on methodological individualism sometimes reflected a strong disposition towards eliminative reductionism with respect to social entities and properties: the early twentieth century exponents like J.W.N. Watkins wanted to find logical formulations through which social terms could be eliminated in favor of a logical compound of statements about individuals. And what was the motivation for this effort? It appears to be a version of the physicist’s preference for reduction to ensembles of simple homogeneous "atoms" transported to the social and behavioral sciences. This demand for reduction might take the form of conceptual reduction or compositional reduction. The latter takes the form of demonstrations of how higher level properties are made up of lower level systems. The conceptual reduction program didn't work out well, any more than Carnap's phenomenological physics did.

In addition to this bias derived from positivist philosophy of science, there was also a political subtext in some formulations of the theory in the 1950s. Karl Popper and JWN Watkins advocated for MI because they thought this methodology was less conducive to the "collectivist" theories of Marx and the socialists. If collectivities don't exist, then collectivism is foolish.

Another phase of thinking was more ontological than conceptual. These thinkers wanted to make it clear that social things, causes, and structures depended on the activities of individuals and nothing else. Another way of putting the point is to say that social entities are composed of ensembles of individuals and nothing else. Their concern was to avoid the social analogue of vitalism -- the idea in the life sciences that there is some special "sauce" of life activity that is wholly independent from the molecular and physical structures that make up the organism. Essentially this crowd wants to hold that the properties of the whole are fixed solely and completely by the physical structures that make it up. The theory of supervenience pretty well captures this ontological position: no differences at the upper level without some difference at the lower level. (This position doesn't imply its converse statement: if two physical systems differ then their upper-level systems must differ too. This is the point of multiple functional realizability.) The position does rule out some forms of emergentism, however. The idea of microfoundations comes into this line of thought. If we make a claim about the structural or causal properties of an upper-level thing, we need to be confident that there are microfoundations that would show how this feature comes about. In the strongest case, we need to actually provide the microfoundations.

There is another important stream of MI thinking that derives from a set of ideas about how higher-level facts ought to be explained: they should be explained on the basis of demonstrations of how the upper-level entity is given its properties by the organized system of elements from which it is comprised. This is essentially what the analytical sociologists seem to demand, by insisting on the logic of Coleman's boat. This approach privileges a certain kind of explanation--constructive or compositional explanations.

There is one aspect of the tradition that I haven't mentioned yet: the idea that we can carve out the individual as separate from and prior to the social -- a view sometimes referred to as "atomistic". In classical physics the analogous claim is supportable. Sodium atoms are homogeneous and interchangeable. But it is not plausible in the human world. Social facts intertwine with the mind and actions of individuals all the way down. So from the start, it would seem that the program of MI should be formulated in terms of reduction from the big-social to the small-social, not the non-social.

So what kinds of social claims do these various formulations rule out?

All of them rule out spooky holism, those social theories that claim that social entities exist that are wholly independent of the features of individuals.

Several of them rule out strong emergentism -- the view that there are social properties that could not in principle be derived from full knowledge about the states and properties of the constituent individuals.

They by and large rule out explanatory autonomy for the social level. This is the idea that there might be fully satisfactory causal arguments that proceed from statements about the properties of one set of social factors and the explains another set of social outcomes on this basis. (The ontological thesis does not have this implication.)

As Heath argues in his SEP essay, they rule out macro-level statistical explanations and what he calls micro-level sub-intentional explanations.

In my view, the only claims about methodological individualism that seem unequivocally plausible today are the ontological requirements -- the various formulations of the notion that social things are composed of the actions and thoughts of individuals and nothing else. This implies as well that the supervenience claim and the microfoundations claim are plausible as well.

But to concede that x's are composed of y's does not entail the need for any kind of reductionism from x to y. And this extends to the idea of explanatory reduction as well. So methodological individualism does not create valid limits on the structure of social explanations, and meso-level explanations are not excluded.

So it seems as though we can now draw several conclusions about the field of methodological individualism. The ontological thesis is roughly true, but it is compatible with a range of different ideas about within- and cross-level explanation. So reductionism doesn't follow. The micro-level can't be a hypothetical pre-social or non-social individual. Finally, there is no reason to associate the plausible core of MI theory with one specific theory of action, the rational-intentional theory. As pragmatist sociologists are now arguing, there are compelling theories of the actor that do not privilege the model of conscious deliberative choice.