In somecomplexdomains,like the gameof Go,evaluating a position is not simple. In other games,like Chessfor example,material balancegives goodandfast to compute insight onthe valueof a position.In Goall the stoneshave the samevalue, so materialbalanceis not a goodheuristic. To evaluate a Goposition, a computerneeds a lot of knowledgeand muchmoretime. Evaluation in computer Gois interesting froman AIpointof view,becauseit shows the power of knowledge in complex and real world domains.