Specification and Reasoning. Consider a simple surveillance application. Assume a square area is divided into four equal parts. The high-level goal is to cover the area, which is satisfied by subgoals...

Specification and Reasoning. Consider a simple surveillance application. Assume a square area is divided into four equal parts. The high-level goal is to cover the area, which is satisfied by subgoals requiring an observer bot in opposite corners. Assume there are two bots initially in one square. A bot can detect its position (producing a position fact) and is able to move to an adjacent square (but not diagonally). Define logical rules expressing that to satisfy a position goal it is sufficient to move to that position, and to satisfy a goal of moving from A to B it is sufficient to move to B if B is adjacent. If B is not adjacent, it is sufficient to move to adjacent square C and then move from C to B.