Karma in the Indian religions is the concept of "action" or "deed" (from Wikipedia). Which means through our thoughts, words, our own actions, or actions others do under our instructions we cause an effect...either positive or negative. However, at every moment in time we have an opportunity to do something about our destiny by doing the right thing at the right time. We produce negative karma because we lack knowledge and clarity. Is that to say the more we learn, the broader our knowledge base, the more clarity we will acquire to better effect positive karma for ourselves (and our next life) and those around us?
I guess that begs the question...do we learn from our actions and the karma that action or actions have created? Because the karma we create will effect the future, and our next life, then is it not important to do our best...to make the right choices for the right reasons so that the outcome will be positive.
"Karma is not fate, for humans act with free will creating their own destiny." Therefore, we can effect the possible outcome of our actions by making right choices for the right reasons. To help us make right choices that will effect our life and others around us, we must acheive balance between yin on one hand and yang on the other hand. It is the action of striving for this balance that will help us create positive karma that will make our lives better, as well as those we come into contact with as we travel down life's path...where ever that path will take us from this moment on.