Isolate variables in behavioral experiments by changing only

Why This Is a Principle

This is a principle derived from Automatic Narrative Generation Precedes Conscious Evaluation (brain generates causal narratives before conscious evaluation) and Automatic Fusion of Observation and Interpretation (observation fuses with interpretation automatically). The principle follows: because causal attribution is automatic and often inaccuous, you must design experiments that enable valid attribution by controlling confounds. It's actionable (tells you HOW to design experiments), general (applies across all behavioral domains), and derived rather than foundational.