The ideal of Karma-Yoga
A goal can be reached by different routes viz, by work, love, psychology & knowledge. These are merely tendencies but all of us will have to work with some aspects of each but a dominant way of getting to the goal.
Evil > The Line of action taken is not proper.
Good > When the line of action is taken properly for the good.
Freedom is the one goal of all nature, sentient or insentient, everything is struggling towards that goal.
Freedom is relative, what freedom means to me may be different for another person.
When one does good work and helps others his circle of influence grows beyond me/mine. Unselfishness is the definite goal. What which is selfish is immoral and vice versa(unselfish is moral). However, the environment plays a major role in determining whether an action can be considered unselfish or selfish. So in most cases, a general scenario is taken into considering while keeping the time, place & circumstances.
In an Absolute sense, one cannot deem an activity as good or bad but certainly, in a relative sense we can categorize the activity to be either good or bad. The balance sheet always tallies between good/bad, pain/happiness and other aspects. We just push it from one side to the other side. One can only know the value of pleasure after experiencing the pain. One can only know how good something is until he has seen the bad or unpleasant side.
Just as inequality is required for creation itself, so the struggle to limit or finish it is also necessary. If the world would have been perfect in the first place why would it be created? If there were no struggle to become free and get back to where we came from (God), there would be no creation either. A duty is never finished, one part done leads to next on the verge of waiting to be completed and so on. There are only 2 ways out of this, give up all concerns and let it go and give up our desires. It is easier said than done, another way is to plunge into the world and learn the secret of work.
Every good work done without attachment will break the links and take us towards ultimate freedom. Every good thought that we send towards others will break of the links in the existing chains leading us closer to the freedom and making us purer. Do good and be good until it becomes a habit.