What is school of marital arts that teaches to evade attacker?

I can't remember the name of school of martial arts that teaches to completely evade an attacker. Years ago I heard about a philosophy that teaches ... as an attacker comes at you - rather than attack head on; just move to the side and evade the attacker. Let the attacker wear himself out. It was a whole philosophy. It was at the core of this philosophy - use the attacker's energy to defeat him. Searched Wikipedia, etc. But can't find the answer. Not sure how else to articulate this question better.