Interdependence theory
Interdependence theory is a social psychological framework developed by John W. Thibaut and Harold H. Kelley in 1959 that analyzes how interacting individuals mutually influence each other's thoughts, emotions, behaviors, and outcomes through patterns of dependence on one another's actions.[1] The theory posits that social interactions can be represented as situations where outcomes are jointly determined, often modeled using outcome matrices that depict possible rewards and costs for each participant based on their choices.[2] Originally introduced in Thibaut and Kelley's book The Social Psychology of Groups, the theory built on exchange and game theories to explain group dynamics and interpersonal relations, introducing core concepts such as the comparison level (CL)—an individual's expectation of outcome quality based on past experiences—and the comparison level for alternatives (CLalt)—a benchmark for evaluating whether better options exist outside the current interaction.[1] It was further formalized in their 1978 work Interpersonal Relations: A Theory of Interdependence, which expanded the analysis to include the transformation of preferences, where individuals shift from self-interested "given" preferences to broader "effective" preferences influenced by relational goals, cognition, and affect.[2] Subsequent developments, such as Kelley et al.'s 2003 An Atlas of Interpersonal Situations, added dimensions like temporal structure (e.g., one-shot vs. ongoing interactions) and information availability, creating a taxonomy of 21 common interpersonal situations.[1] The theory's key principles include the principle of structure, which emphasizes how situational features like the level of dependence, mutuality of dependence, and covariation of interests shape behavior; the principle of transformation, highlighting adaptive shifts in decision-making; the principle of interaction, positing that interaction outcomes result from the interplay of individuals and situational factors; and the principle of adaptation, where repeated interactions foster stable dispositions, norms, and motives.[2] In applications to close relationships, interdependence theory explains satisfaction and commitment as functions of outcomes relative to CL and CLalt, accounting for phenomena like why individuals remain in unsatisfying partnerships due to low alternatives or high investments.[2] It has also informed research on cooperation, conflict resolution, power dynamics, and prosocial behavior across diverse contexts, from dyadic exchanges to larger social systems.[1]Introduction and Historical Context
Core Overview of the Theory
Interdependence theory is a foundational framework in social psychology that examines how individuals' outcomes in interpersonal situations are contingent upon both their own behaviors and those of others, within the constraints and opportunities provided by the situational structure.[1] This model highlights mutual dependence, where actions create interconnected reward and cost structures, shifting focus from isolated individual decisions to the dynamics of shared influence in dyads and groups.[3] Central to the theory is the principle that interaction outcomes emerge from the interplay of personal factors and environmental contingencies, formalized as I = f(A, B, S), where I represents the resulting interaction, A and B denote the dispositions and motivations of the two actors, and S captures the objective properties of the situation.[1] Introduced by John Thibaut and Harold Kelley in 1959, this formulation underscores the theory's departure from individualistic paradigms, emphasizing instead how interdependent contexts shape social behavior across relationships and groups.[4] The primary objective of interdependence theory is to elucidate how people assess and manage rewards, costs, and dependencies to optimize outcomes in these mutually influential settings, providing a lens for understanding cooperation, conflict, and adaptation in everyday social exchanges.[3] Built on four core principles—structure, transformation, interaction, and adaptation—the theory offers a systematic approach to dissecting these processes (detailed later).[1]Development and Key Contributors
Interdependence theory originated with the collaborative work of social psychologists John W. Thibaut and Harold H. Kelley, who introduced its foundational concepts in their 1959 book, The Social Psychology of Groups. This seminal text analyzed power, dependence, and social exchange within groups, laying the groundwork for understanding how individuals' outcomes are shaped by mutual reliance.[1] The theory drew heavily from Kurt Lewin's field theory of the 1930s and 1940s, which viewed behavior as a function of the person and their environment (B = f(P, E)), adapting it to highlight interdependence as central to group dynamics and interpersonal situations.[1] This Lewin-inspired integration is reflected in the theory's core formulation, I = f(S, A, B), emphasizing interaction as a product of situational structure, actors, and behaviors.[1] Thibaut and Kelley's ideas were formalized and expanded in their 1978 book, Interpersonal Relations: A Theory of Interdependence, which systematically outlined the theory's principles for analyzing dyadic and group interactions.[5] This publication marked a pivotal milestone, shifting focus from descriptive group processes to a rigorous analytical framework for interpersonal relations.[6] Harold H. Kelley further advanced the theory in the early 2000s, notably through An Atlas of Interpersonal Situations (2003), co-authored with John G. Holmes, Norbert L. Kerr, Harry T. Reis, Caryl E. Rusbult, and Paul A. M. Van Lange; this work cataloged 21 prototypical interpersonal situations and introduced two additional dimensions—temporal structure and information availability—to the theory's situational analysis. Van Lange, a key collaborator, continued these expansions through the 2010s and into the 2020s, integrating interdependence theory with evolutionary psychology and social dilemma research, including the 2017 development of Functional Interdependence Theory.[1][7] It is important to distinguish this theory from the social interdependence theory developed by David W. Johnson and Roger T. Johnson in the 1970s, which centers on goal structures to promote cooperative learning in educational contexts rather than broad interpersonal situation analysis.[8]Fundamental Principles
Principle of Structure
In interdependence theory, the Principle of Structure emphasizes the objective features of interpersonal situations that determine how individuals' actions influence each other's outcomes, independent of personal motivations or interpretations. These structural properties are captured through a "given matrix," which outlines the possible payoffs or outcomes for each person based on the combination of their own and their partner's behaviors, assuming self-interested maximization. This matrix represents the inherent constraints and opportunities of the situation, such as who controls which aspects of the outcomes—whether through the actor's own actions (actor control), the partner's actions (partner control), or joint efforts (joint control).[1] The structure of a situation is characterized by six key dimensions that shape the nature of interdependence. First, the level of dependence refers to the extent to which a person's outcomes rely on their partner's actions, ranging from low (where outcomes are largely self-determined) to high (where the partner exerts significant influence). For instance, in casual encounters, dependence is typically low, allowing individuals to achieve satisfactory outcomes independently, whereas in close romantic relationships, high dependence means outcomes are heavily contingent on the partner's behavior. Second, mutuality of dependence describes whether this reliance is symmetrical (mutual, as in equitable partnerships) or asymmetrical (unilateral, as in hierarchical boss-employee dynamics), which can amplify power imbalances.[1] Third, covariation of interests, also known as correspondence, assesses the alignment of partners' self-interests: high correspondence occurs when both benefit from the same actions (promotive structure, fostering cooperation), while low correspondence involves conflicting interests (contrient structure, encouraging competition). A classic illustration is the Prisoner's Dilemma, a non-correspondent payoff matrix where mutual cooperation yields moderate joint gains, but each individual's dominant self-interested choice leads to mutual defection and poorer outcomes for both. Fourth, the basis of dependence delineates how control over outcomes is distributed, such as through actor control (outcomes depend primarily on one's own actions), partner control (outcomes depend on the partner's actions), or joint control (outcomes require coordinated efforts), influencing potential for exploitation or collaboration.[1] The remaining dimensions include temporal structure, which distinguishes between one-shot interactions and ongoing sequences where past actions affect future outcomes, and information availability, which varies from full knowledge of the matrix to partial or uncertain information about payoffs and partner behaviors. These dimensions collectively define the objective "rules of the game" in any interaction, setting the stage for how actors might subjectively transform the structure through their decisions, as explored in related principles. Overall, the Principle of Structure underscores that interdependence arises from these fixed situational properties, providing a foundation for predicting behavioral patterns without invoking psychological dispositions.[1]Principle of Transformation
The principle of transformation in interdependence theory describes the psychological process through which individuals alter their preferences from those dictated by immediate self-interest in a given situation to effective preferences that incorporate broader relational or social considerations. This transformation shifts the objective "given matrix" of outcomes—representing what each person can obtain based solely on their own and the partner's actions—into a subjective "effective matrix" that guides actual decision-making. As articulated by Kelley and Thibaut, this process allows people to "make" the situation in ways that align with their motivations, values, and long-term goals, beyond mere pursuit of personal gain. Transformations occur in two primary forms: orientation-based and rule-based. Orientation-based transformations stem from motivational orientations, such as cooperation, which prioritizes maximizing joint outcomes for both parties, or equity, which seeks to minimize differences in outcomes to ensure fairness. In contrast, rule-based transformations involve applying normative or strategic rules to guide behavior, such as tit-for-tat reciprocity in repeated interactions, where one mirrors the partner's previous actions to foster mutual cooperation over time. These types enable individuals to reinterpret competitive or conflicting situations in prosocial ways, influenced by factors like trust and shared values.[1] Motivational factors driving transformation include evaluations of rewards and costs across multiple domains, which expand beyond immediate tangible payoffs to encompass psychological and social dimensions. Material rewards or costs involve concrete elements like resources or time, while psychological ones pertain to emotional fulfillment, such as feelings of satisfaction from fairness or stress from inequity. Social rewards and costs include relational approval, reputation, or group norms that encourage behaviors benefiting the partner or collective. In this evaluation, individuals consider a transition list—a formal representation of possible action sequences and outcome shifts available to each person, accounting for behavioral control and interdependence. This list highlights viable paths from current states to alternative outcomes, informing how transformations reshape choices.[9][1] For instance, in a interpersonal conflict with a inherently competitive structure—such as negotiating household chores where self-interested choices might lead to imbalance—one partner may transform the situation cooperatively by empathizing with the other's workload and proposing a shared solution, thereby prioritizing mutual welfare and equity over individual maximization. This empathetic shift not only alters the effective outcomes but also sustains the relationship through reinforced prosocial norms.[6]Principle of Interaction
The Principle of Interaction in interdependence theory posits that social interactions arise from the dynamic interplay between two actors and the objective properties of their situation, encapsulated in the SABI model formulated as I = f(A, B, S).[1] Here, I represents the resulting interaction, while A and B denote the individual characteristics of the two persons involved, including their stable dispositions (such as personality traits influencing decision-making), relevant skills (like problem-solving abilities), and transformed preferences (preferences altered through motivational processes to align with broader goals).[10] The situational component S refers to the structural features of the interdependence, such as the distribution of outcomes contingent on each actor's choices.[11] This model underscores that no single element—actor or situation—determines behavior in isolation; instead, interactions emerge from their mutual influence.[6] In this process, actors evaluate and select behaviors from transition lists, which formally represent the possible action options available to each and the corresponding shifts in outcomes they produce.[12] These lists extend beyond static outcome matrices by capturing the sequential and contingent nature of choices, where one actor's action alters the payoff landscape for both, leading to joint outcomes that reflect mutual interdependence.[13] The theory distinguishes between the given matrix, which outlines the objective, self-interest-based outcomes inherent in the situation structure, and the effective matrix, which incorporates the actors' transformations to yield the actual, motivationally adjusted outcomes realized in the interaction.[1] Through this mechanism, the Principle of Interaction explains how situational constraints and personal factors converge to shape behavioral choices and resultant interdependence.[11] A key psychological process within this principle involves attributions, where actors interpret observed outcomes to infer their partner's underlying intentions, dispositions, or motivations, thereby influencing subsequent perceptions and action selections. For instance, if an outcome favors one actor disproportionately, the other may attribute it to exploitative intent rather than situational necessity, fostering distrust and altering future transformations toward defensiveness.[10] These inferences, grounded in the effective outcomes of prior exchanges, create a feedback loop that refines actors' expectations and strategies, though they can introduce biases if not calibrated to the full situational context.[6] This dynamic is exemplified in negotiation contexts, where mutual transformations—such as both parties prioritizing joint gains over individual maximization—can convert a competitive structure (e.g., akin to a prisoner's dilemma) into a cooperative equilibrium benefiting all involved.[1] In such scenarios, actors' selections from transition lists, informed by attributions of cooperative intent, enable shifts from zero-sum outcomes to value-creating agreements, highlighting the principle's emphasis on how personal and structural elements foster emergent collaboration.[11]Principle of Adaptation
In interdependence theory, the principle of adaptation posits that repeated exposures to similar interdependent situations foster the development of habitual response tendencies, which stabilize behavioral patterns over time. These adaptations arise from accumulated experiences, enabling individuals to navigate recurring structures more efficiently by defaulting to proven transformations without deliberate reevaluation each time.[1] Adaptation manifests through two primary channels: personal scripts and social norms. Scripts represent individualized habitual reactions shaped by prior personal experiences in analogous situations, often executed with minimal conscious deliberation; for instance, in ongoing romantic partnerships, partners may routinely defer to each other's preferences in decision-making after repeated positive outcomes from such yielding.[1] Social norms, in contrast, are culturally transmitted rules that prescribe responses to broad classes of interdependent scenarios, such as equity norms in resource allocation or reciprocity expectations in exchanges, guiding behavior across diverse actors within a shared context.[1] Frequent interactions in these situations progressively reduce uncertainty about others' likely actions, promoting the entrenchment of default transformational rules that align given matrices with effective choices.[5] These mechanisms yield outcomes that enhance relational efficiency by streamlining decision-making in predictable environments, yet they also introduce risks of rigidity, where outdated habits persist despite changing circumstances. In organizational settings, for example, established protocols for task coordination may optimize team performance initially but hinder flexibility during crises. Adaptation further intersects with power dynamics, as actors with greater dependence or lower power are more likely to conform to the norms or scripts imposed by dominant partners, thereby reinforcing asymmetries in influence over time.[14] Empirical support for this principle emerges from research on repeated games, particularly the prisoner's dilemma, where players converge toward cooperative norms through generous strategies like tit-for-tat with added forgiveness, achieving higher joint outcomes compared to strict reciprocity after multiple rounds. Such studies demonstrate how iterative interactions cultivate adaptive dispositions that prioritize long-term mutual benefit over immediate self-interest.[15]Key Concepts and Analytical Tools
Outcome Matrices and Interdependence Dimensions
Outcome matrices serve as a foundational analytical tool in interdependence theory for representing the structure of interpersonal situations, where outcomes for both actors depend on their joint actions. The given matrix, also known as the objective payoff matrix, depicts all possible outcome combinations for two actors, Person A and Person B, based on their behavioral choices. Rows typically represent A's possible actions, while columns represent B's, with each cell containing paired outcomes (A's payoff, B's payoff) that reflect the direct consequences of those actions without considering motivational transformations. This matrix-derived approach stems from the principle of structure in interdependence theory, which emphasizes how situational properties influence behavior.[16] For instance, in a coordination situation like a mutual aid scenario, the given matrix might illustrate symmetric benefits when both parties cooperate, as shown below:| B Cooperates | B Defects | |
|---|---|---|
| A Cooperates | (10, 10) | (0, 15) |
| A Defects | (15, 0) | (5, 5) |
| B Cooperates | B Defects | |
|---|---|---|
| A Cooperates | (3, 3) | (0, 5) |
| A Defects | (5, 0) | (1, 1) |