We can only cast a Shadow where there is light, and in the Darkness it will shine even Brighter.
In order to understand and appreciate the good in life you must understand what it would be like to live without it. After all without the pain in life it would be completely unclear why we should be happy at all. Looking back the Answers are all clear, Learn from the past to change the present to make a better Future. This is what i believe we can do to better ourselves and in turn the rest of the world. We are just one part of a whole and every action we take is History.