  The combined approach of the Qualitative Reasoning and Probabilistic
Functions for the knowledge representation is proposed. The method aims at
represent uncertain, qualitative knowledge that is essential for the moving
blocks task's execution. The attempt to formalize the commonsense knowledge is
performed with the Situation Calculus language for reasoning and robot's
beliefs representation. The method is implemented in the Prolog programming
language and tested for a specific simulated scenario. In most cases the
implementation enables us to solve a given task, i.e., move blocks to desired
positions. The example of robot's reasoning and main parts of the implemented
program's code are presented.
