1. A method for building hierarchies, comprising: receiving a selection of a focus object; loading the focus object into a builder from a catalog of objects; revealing a set of objects as possible hierarchical extensions to the focus object based on relationships of the set of objects to the focus objects; receiving a selection of one of the set of objects; identifying a set of instances corresponding to the selected object; and filtering the set of objects for compatibility with the focus object using hierarchical relationships as defined in the catalog of objects.