1. in artificial intelligence, a technique to solve problems that sets up subgoals as means to achieve the goals (ends) and compares subgoals and goals using a recursive goal-reduction search procedure. See General Problem Solver.

2. more generally, any problem-solving strategy that assesses the difference between the current state and a desired end state and attempts to discover means to reduce that difference. Such a strategy would not discard means to the end that appear to be “blocked,” but it would consider possible ways to overcome any such intermediate problem.