Abstract

This treatise introduces the Sougy Personality Type Spectrum (SPTS), a novel seven-type personality model organized around the Φ:Ψ ratio—the proportion of philosophical function (Φ) to psychological function (Ψ) operative within an individual’s cognitive-existential orientation. Grounded in the Double Helix of Understanding framework (Boether, 2025a), which conceptualizes philosophical and psychological functions as complementary strands of a unified consciousness system, the SPTS advances a non-pathologizing spectrum from predominantly psychological orientation (Type 1) through equilibrial integration (Type 4) to predominantly philosophical orientation (Type 7). The model introduces the DH exponent as an independent variable measuring the degree of functional integration between Φ and Ψ, irrespective of spectrum position. This psychometric investigation develops the theoretical architecture of the SPTS and evaluates its discriminant validity against the Myers-Briggs Type Indicator (MBTI) and the Five-Factor Model (Big Five), arguing that neither existing framework adequately captures the philosophical dimension of personality variation. The treatise further demonstrates that the Φ:Ψ ratio predicts meaningful differences in cognitive style, meaning-making capacity, and existential well-being beyond what current instruments measure. Future directions include normative studies across populations, cross-cultural validation, and educational applications for differentiated instruction.