1. A computer-implemented method for building a polyhierarchical classification of objects, the method comprising: a) identifying properties of objects considered useful for distinguishing objects under classification; b) identifying a plurality of criteria for specializing the identified properties of the objects, wherein each criterion of the plurality of criteria is defined by a set of mutually exclusive attributes; c) choosing a form of attributive expressions for describing classification categories, wherein the attributive expressions are information structures encoding logical formulas that define compositions of object properties in terms of attributes from the plurality of criteria, while the form of the attributive expressions is customizable; d) identifying a domain of applicability for each criterion, wherein the domains of applicability are representable by attributive expressions composed of attributes from other criteria or the empty attributive expression, and a dependence relationship between criteria is defined by the inclusion of attributes in the attributive expressions, wherein a selected criterion depends on another criterion if the attributive expression defining its domain of applicability includes at least one attribute by the other criterion, and a generating polyhierarchy of criteria is automatically established by the dependence relationships between the criteria, wherein, the attributive expressions identifying domains of applicability of criteria, define corresponding root categories in the polyhierarchical classification, wherein each criterion originates from its respective root category, and when established, the generating polyhierarchy of criteria implicitly defines an induced polyhierarchy of classification categories without requiring an explicit enumeration of the categories and an ordering between them; and e) storing in a computer-readable medium the polyhierarchical classification of objects.