This slide deck by Jean‑Paul Carvalho (UC Irvine) develops a theory of "norms of identity" to explain religious dress practices, focusing on veiling among Muslim women. It begins by defining religious identity as a set of restrictive, stigmatizing markers that can solve collective‑action problems (Iannaccone 1992). Historical photographs illustrate strict sects and the 1967 Summer of Love, setting a contrast between traditional and new veiling movements, the latter driven by urban, educated, middle‑class women during an Islamic revival. Three explanatory lenses are presented—decision‑theoretic, price‑theoretic, and norm‑theoretic—culminating in Carvalho’s proposal that veiling functions as a public commitment to community norms, limiting temptation, shaping interaction structures, and providing self‑control cues. A formal 2×2 symmetric coordination game models the tension between a religiously permissible action (R) and a prohibited action (S). A stochastic revision protocol determines how agents update behavior based on random matching either within the community (M) or the broader population (N). Payoff functions incorporate intrinsic (self‑judgment) and extrinsic (social judgment) components, with type‑specific parameters (λr, λs) and the proportion of religious types (q). Integration thresholds (w) are derived, showing when religious and non‑religious types segregate or integrate depending on the cost of community‑only matching. Veiling is introduced as a continuous public commitment variable v∈[0,1] that reduces the probability of uniform (cross‑community) matching, thereby altering the ex‑ante probability of choosing the prohibited action S. The model yields optimal veiling levels under low‑veiling (|λr|≤λs) and high‑veiling (|λr|>λs) regimes, with comparative statics indicating that veiling rises with the prevalence of the prohibited action in the broader population (y), religiosity (q, |λ_r|), mixing probability (ρ), and the attractiveness of the secular norm (α). Empirical evidence is presented: veiling among religious women in Turkey and Belgium increases with education, labor market participation, non‑Muslim friendships, and non‑Muslim neighborhood share (Aksoy & Gambetta 2016). The impact of policy is examined through the 2004 French headscarf ban, which reduced secondary school enrollment and labor force participation for Muslim women (Abdelgadir & Fouka 2018). Long‑run dynamics suggest that veiling is temporary, disappearing as community and population behaviors converge, but bans can slow convergence and raise overall religiosity via cultural transmission. The presentation draws parallels with Jewish emancipation strategies—Reform Judaism (full integration), Modern Orthodoxy (partial integration), and Ultra‑Orthodoxy (anti‑integration)—as concrete examples of integration approaches. Finally, it situates norms of identity within the second‑best theory framework, arguing that seemingly inefficient identity‑based institutions may be optimal given monitoring and commitment constraints.
Topics
Religious Identity and Restrictive Markers
Defines religious identity as a set of restrictive, stigmatizing practices that serve as group‑membership signals and solve collective‑action problems.
Traditional vs. New Veiling Movements
Contrasts historical, traditional veiling practices with the contemporary, urban, educated, middle‑class veiling movement that emerged in the 1970s‑80s.
Norm‑Theoretic Explanation of Veiling
Presents veiling as a public commitment mechanism that limits temptation, structures interaction sets, and provides self‑control cues, alongside decision‑ and price‑theoretic perspectives.
Formal Coordination Game of Social Norms
Introduces a 2×2 symmetric pure coordination game (actions S and R) and a stochastic revision protocol governing how agents update behavior based on community versus population matching.
Self and Social Payoffs in Community Interactions
Specifies intrinsic (self‑judgment) and extrinsic (social judgment) payoff components for religious (r) and non‑religious (s) types, incorporating parameters λ_r, λ_s, and the religious proportion q.
Integration Thresholds and Segregation Dynamics
Derives cost thresholds w̲(q) and w̄(q) that determine when religious and non‑religious types segregate or integrate, based on matching costs and type composition.
Veiling as a Public Commitment Variable
Models veiling intensity v∈[0,1] as reducing the probability of uniform (cross‑community) matching, affecting the ex‑ante probability of prohibited behavior and overall payoff.
Optimal Veiling Levels and Regimes
Provides closed‑form optimal veiling solutions under low‑veiling (|λ_r|≤λ_s) and high‑veiling (|λ_r|>λ_s) conditions, with tables showing how optimal v varies with religiosity q.