I had that relization today. It's more than a physically true statement.
The use of being, is more than just to exist. There must be something more; we are more than mere beings and are bigger than our bodies, on an abstract, astral, and spiritually-based level as well as millions of other planes of existence. There can be no reason to live, if we only live to die uselessly. Natural selection kills what isn't meant to be. We still live, so that is sufficient evidence (in my mind at least) that there is a reason for us being here. You may believe in a supreme being, higher than material things. Neither is there complete evidence of all mankind being made by supernatural causes, or evidence of it being completely by some chance reaction in the darkness of the beginning. It's all very confusing.
But... What If there is a reason that we exist, aside from the same reason we believe everything was created. Maybe the creation and the purpose are seperately intertwined, and not directly hand-in-hand? If the reason for us to live is to enjoy and prosper in happiness, why are we so blind to that fundemental truth? Just the way the world is designed should be evidence enough that we are here for a reason. Though I don't know and can't tell you exactly what or who or how. In my eyes, to every thing, there is a reason; just as to every mood, there is a season. We will, more likely than not, never know the answers to these questions. Maybe that's the reason we shouldn't ask them, and if we wonder these things we get pains of thinking about it. What If we choose, by our own decision and freedoms, to live how we believe we should? Why would that not be a reason to live and enjoy what we have?