A computer-based method and apparatus for assessing problems and situations in a defined knowledge domain, employing both (a) an inferential database of elemental data components, as domain-wide as possible, which are relevant to the domain, and (b) periodic statistical reviews of reported assessment results in relation to that database to establish the certainty levels of such results. The invention employs nonlinear assessment techniques likenable to human reasoning, and thereby, as well as in other ways, conducts assessment tasks in a manner that differentiates it from conventional, machine-based, linear problem resolution.