What I consider to be my main philosophical discovery

I have a philosophical theory that I would like to share, which is that it is possible to do what is right even when everything is corrupt, and that doing the good or even just the best thing that you can do does ultimately benefit everyone, even if people or animals are harmed in the process because of evil systems and forced choices from unavoidable spectrums of greater and lesser evils. In the most evil situations, this idea of mine probably can only seem offensive, but I think it is a very helpful truth for most people who have had to make compromises in order to survive and do the greater goods that they have determined are worth their participation in very faulty societies.  I do not think everyone believes this idea, but I am almost certain of it, and it has helped me keep living for a long time.