You are the eyes through which the universe sees itself. You are the mind with which all of creation seeks to comprehend and know itself. Your brief time on this tiny speck of dust may seem insignificant, yet in truth it is not insignificant at all. It is everything. You may feel great pain and misery and yet no matter how great the pain, it is a price well worth paying. For in return for that price, you are. You exist and you are miraculously aware of that existence. The spark of life, however dim, however much abused, however burdensome, is priceless beyond measure. With it, a whole limitless plain of existence spreads out in the direction of the infinite. Without it, there is nothing to be known, nothing to be seen, no beauty, no reason or purpose.
There are those who would say you are a waste of resources. And yet without you, there would be no concept of resources. There are those who would say that you abuse the purity of your environment. But that purity cannot be abused, for it remains steadfast and inviolable no matter what you do. Yes, your environment is constantly changing and interacting with your physical presence. But you cannot alter the fundamental laws that govern it. You can only move grains of sand from one place to another.
What you can do, though, is give it all meaning. Just as a rock provides the foundation for physical structure, your awareness and aliveness provide the foundation for meaningful purpose.
Some may question the purpose you choose, and accuse you of selecting a purpose that is in conflict with the purpose of others. Is it selfish, you wonder, to touch that white-hot spark of light that lives within you, and to follow where it leads? Is it selfish to seek fulfillment when other creatures seem to be denied any sort of fulfillment? It is not selfish, for what truly fulfills you benefits all that is.