The expediency of developing tools for automatic formation of judgments as one of the mental acts of conceptual thinking of intelligent mobile systems for various purposes has been substantiated. The use of such means of inference makes it possible to form the knowledge that is missing for decision-making in the process of planning purposeful behavior in a priori undescribed conditions of a problematic environment. To solve this problem, conditionally dependent predicates were used as the initial elements of knowledge representation, providing the ability to derive both simple and complex judgments that determine various patterns of purposeful transformation of the current conditions of functioning. Tools have been developed that allow to form complex judgments from simple judgments obtained by designating variables of the sort "objects" and "relations" of conditionally dependent predicates by objects located in a problematic environment and estimates of relations that are observed in it between these objects. As an example showing the effectiveness of using the proposed tools for obtaining new knowledge that is missing for the conclusion of solutions, an algorithm for planning the purposeful behavior of an autonomous mobile underwater robot has been built, which provides it with the ability to perform rather complex tasks related to the search for various objects with certain properties and their transportation to a given point of the problem Wednesday.