Pragmatics & Cognition, Vol. 19, No. 1, pp. 92–116, 2011
21 Pages Posted: 11 Aug 2011
Date Written: August 11, 2011
Reasoning from negative evidence takes place where an expected outcome is tested for, and when it is not found, a conclusion is drawn based on the significance of the failure to find it. By using Gricean maxims and implicatures, we show how a set of alternatives, which we call a paradigm, provides the deep inferential structure on which reasoning from lack of evidence is based. We show that the strength of reasoning from negative evidence depends on how the arguer defines his conclusion and what he considers to be in the paradigm of negated alternatives. If we negate only two of the several possible alternatives, even if they are the most probable, the conclusion will be weak. However, if we deny all possible alternatives, the reasoning will be strong, and even in some cases deductively valid.
Keywords: argumentation, argument from ignorance, burden of proof, classification under lack of knowledge, defeasible reasoning, Gricean maxims, lack of evidence, negation, scalar predicates
Suggested Citation: Suggested Citation
Macagno, Fabrizio and Walton, Douglas, Reasoning from Paradigms and Negative Evidence (August 11, 2011). Pragmatics & Cognition, Vol. 19, No. 1, pp. 92–116, 2011. Available at SSRN: https://ssrn.com/abstract=1908052