Testing Seventeen Centuries of Claims: An Ecologically Valid Multi-Method Empirical Study of Basilica-Plan Sacred Architecture

For seventeen centuries, basilica-plan churches have remained among Christianity’s most enduring architectural forms. Scholars have long argued that features such as bell towers, axial orientation toward the altar, upward light, noble materials, verticality, monumental scale, beauty, and figurative iconography communicate sacred meaning and shape religious experience, though these claims have remained largely grounded in historical, architectural, and theological discourse. This exploratory study recruited thirty-two committed Catholic participants to visit the Basilica of the National Shrine of the Immaculate Conception and Union Station, a secular control, both in Washington, DC. Using mobile eye-tracking, biometric sensing, phenomenological and perceptual reporting, and a post-visit questionnaire, the study investigated, under fully ecological conditions, which features of the basilica type shape attention, experience, and religious understanding. The findings make four contributions: (1) empirical support for longstanding claims about the basilica type, showing that its features operate as an integrated affordance-rich environment, orienting experience toward what participants identify as God; (2) demonstration that rigorous ecological investigation of sacred architectural experience is achievable without sacrificing empirical validity; (3) documentation of a three-level dissociation between aesthetic and sacred experience—pre-attentive equivalence across both buildings, semi-conscious divergence driven by figurative content, material richness, verticality, and a proposed “prelude schema,” and consciously reported differences in spirituality, connectedness, and experiential profile; and (4) a methodological framework for advancing Experimental Theological Aesthetics across architecture, liturgy, ritual, sacred art, and natural environments.