Pull off and discard the bruised cabbage leaves. Rinse cabbage and thinly slice.
In a large bowl, mix 6 tablespoons rice vinegar, sugar, horseradish, red onion, and ginger. Add cabbage and then salt to taste; mix well. For mellower flavor, let salad stand at least 10 minutes, then mix again.
Rinse the pears, and core them. Coarsely chop 1 pear and mix with salad. Slice remaining pear, moisten with a little rice vinegar, and arrange on salad. Sprinkle with chives.