I believe responses are engendered by the person experiencing them. I agree that compassion doesn't require sadness or sorrow. I do think compassion includes the desire to help. For me, compassion is joining with the other in their suffering their burden, or at least being with and feeling with the other in their suffering their burden, so compassion does include wanting to help. I have had times of experiencing a great deal of compassion that I think could have been moments of life lived in its fullness -- I have experienced a good deal of fullness during such moments but not life lived in its fullness during such moments -- perhaps I don't have enough compassion or enough letting myself feel total fullness. What helps me grow in compassion as a way of life is my believing that we are one and we have the same burdens, so in sharing in others' suffering, others share in mine, and in such being together we are making it all a little more bearable for all.