Basing explanation on deduction, or "covering laws," within the context of formal logical is misleading in several ways.
- The explanans involves a universal scientific law. Not only do explanations extend far beyond science, but it's unlikely that any scientific law is universal. It is better to say that explanations include a "substantive generalization," what Toulmin called a "warrant," where "substantive" means it is generally true. It is precisely the truth or falsity of the explanatory generalizations that is obscured by limiting them to universals.
- Explanation is a matter of making the explanandum rationally acceptable. With an explanation we already know the explanandum is true, so there's no need to justify or prove it. With a plausible explanation the explanans and explanandum are logically consistent, nothing more.
- The logical consistency of an explanation is a matter of deduction. The premises of a deduction, 'if x then y' and 'x', are actually equivalent to the conjunction, 'x and y'. It is this conjunction of the explanans and the explanandum (all of them being true) that creates a plausible explanation. Thus, narratives, absent any generalizations, can constitute explanations on the same logical ground as deductions using generalizations.
