It is not so much on the physical plane that we should try to improve matters, for the physical plane is the world of effects and there is very little we can do about effects. If we want to produce any lasting changes, we have to rise to the world of causes.
We are capable through thought of reaching the world of causes and of affecting and setting in motion pure forces that will sooner or later produce good results. As long as you merely intervene on the physical plane, you will never really put anything right, for people and events will rearrange things to suit themselves without consulting you, and you will never be fully in control of the situation.
Working to change effects is like writing words in the sand; the waves come in and wash them away. It is the causes we have to work on.