The 8-Factor reasoning styles scale: development, validation, and psychometric evaluation

Building on Hacking's historical-philosophical notion of "styles of reasoning" and subsequent three-axis formalisation (Disposition, Perception, Organization), this study develops and validates the Eight-Factor Reasoning Styles Scale (8-FRSS). The instrument operationalises eight theoretically predicted styles that arise from the orthogonal intersections Empirical ↔ Hypothetical, Metaphorical ↔ Analogical, and Inductive ↔ Deductive.

Items (5 per style; 40 total) were generated from the Reasoning Style Model, vetted by five measurement experts, and refined through a pilot face-validity study (n = 50). A sequential mixed-methods design followed: (1) Exploratory Factor Analysis (EFA; n = 441); (2) Confirmatory Factor Analysis (CFA-1; n = 316) with DWLS on polychoric correlations; (3) cross-validation CFA-2 on an independent community sample (n = 604). Reliability (α, ω) and composite reliability/AVE were computed, and concurrent validity was assessed against the Turkish adaptation of the Sternberg-Wagner Thinking Styles Inventory (TSI-TR; 13 subscales).

The EFA revealed the theorised eight-factor solution after removal of two items, explaining 58.2% of variance (KMO = 0.932; Bartlett p < .001). CFA-1 showed excellent fit (χ²/df = 1.77, CFI = 0.918, TLI = 0.901, RMSEA = 0.052, SRMR = 0.047) after minor item pruning; CFA-2 replicated adequate fit in the broader sample (CFI = 0.897, TLI = 0.877, RMSEA = 0.057, SRMR = 0.048). Six subscales met reliability standards (ω/0.70-0.77); two (Hypothetical-Deductive, Empirical-Inductive) showed marginal values (ω = 0.48-0.69), earmarked for revision. Total-scale reliability was high (ω = 0.93; α = 0.91). Convergent evidence came from significant positive correlations with conceptually matched TSI-TR subscales, strongest for Analogical styles with legislative/executive/judicial thinking (r ≈ .51-0.61, p < .01).

The 8-FRSS provides the first psychometrically robust measure that simultaneously captures empirical-hypothetical orientation, metaphorical-analogical framing, and inductive-deductive organisation. Its factorial stability across student and community samples, coupled with satisfactory reliability and demonstrable concurrent validity, supports its use in educational, cognitive, and decision-science research. Future work should refine lower-reliability factors, test longitudinal invariance, and explore predictive links to learning outcomes and susceptibility to misinformation.