1. A method, comprising: by the at least one hardware processor executing instructions stored in at least one memory coupled to the at least one hardware processor to perform: creating objects in form E→A from information indicating a knowledge base stored in the at least one memory, the knowledge base storing a mapping of values to sets of evidences U, where A is a rule among rules in the knowledge base, and E is a subset of the sets of evidences U from the knowledge base that supports the rule A, so that the rule A is supportable by the subset of evidences E; determining relationship constraints κ in form of set relations among a plurality of subsets of evidences E; and in response to at least one request, computing for a target rule L, a first composite object with respect to validity (v), ω 1 v =G 1 →L n , and/or with respect to plausibility (p), ω 1 p =G 1 →L 0 , the first composite object ω 1 v or ω 1 p constructed from a combination of the objects E→A to create a composite sets of evidences G 1 v or G 1 p subject to the relationship constraints κ which support a composite rule L 0 v or L 0 p , the composite rule L 0 v or L 0 p being a combination of the rules implying the target rule L according to deductive reasoning indicated by the mapping of the values to the sets of evidences U, the first composite object ω 1 v or ω 1 p indicative according to the deductive reasoning of a first validity value or a first plausibility value for the target rule L.