物极必反

1.Things will develop in the opposite direction when they become extreme.; A thing turns into its opposite if pushed too far.; Once a certain limit is reached a change in the opposite direction is inevitable.; Things always reverse themselves after reaching an extreme.; Things go in the opposite direction when they become too extreme.; Things turn into their opposites when they reach the extreme.; Things which have reached their extremes turn into their opposites.; When a thing reaches its limit it turns round.