The Evidentiary Boundaries of Scientific Explanation - Domain Transfer, Explanatory Warrant, and Physical Admissibility

Scientific results are often extended from observed settings to new domains, from predictions to causalinterpretations, and from mathematical conditions to proposed physical preparations. This article developsa target-specific analysis of scientific warrant: the evidence and assumptions offered must be appropriate tothe particular strengthened claim, not merely to a related, narrower result. Three distinct obstacles make therequirement precise. First, a saturated two-factor countermodel shows that evidence identifying separatedepartures from a baseline need not identify their joint response; this motivates a bounded joint-transferadequacy (JTA) requirement for such branch combinations. Second, a two-population causal constructiondemonstrates that source experimental evidence and target observational agreement cannot generallysubstitute for assumptions identifying a target intervention effect. Third, canonical position–momentumuncertainty shows why an inadmissible literal preparation must be distinguished from a well-defined butunidentified target, while Gaussian preparations preserve valid controlled comparisons. A documentedlaboratory-to-clinical illustration separates assay, exposure, mechanistic, and clinical-outcome claimswithout imputing errors to the investigators. The three obstacles do not instantiate one mathematicaltheorem: they differ in the object left unwarranted and in the appropriate response. Their integrationprovides a comparative, claim-sensitive account of strengthening scientific explanations, not a newidentification result, a demand for exhaustive knowledge, or a claim of priority over existing work onmodel adequacy and causal warrant.