Many folks around the world wonder what will happen to them when they die. They (we) also want to know why we are all here. The former question doesn't intrigue me as much as the latter because if I cease to exist after I die then there won't be any of my consciousness around to continue wondering the question. If there is an afterlife and that afterlife is governed by God, then really the more important question is the latter and its corollary: What does God want me to do while I'm alive? What is the purpose of my existence?
In an atheistic worldview, there is no inherent purpose to life. In atheism, you define the purpose of your existence, which sounds nice and empowering. Really, though, such an approach to our daily endeavors is the same approach that Wiley Coyote takes to be able to run off the cliff without falling. Eventually, he looks down and realizes that there is nothing there to hold him up.
An interesting case is that of Richard Dawkins, a renowned biologist and atheist. He stated in a recent interview that the answers that science gives to how the kangaroo came to be is much more interesting than the idea that God spoke and there it was. (By the way, I as a believing Latter-Day Saint agree with him on this point.) Manifested in his religious works like The God Delusion is the irony that Mr. Dawkins's purpose in life is to demonstrate that there is no purpose to life. How long will a man like Dawkins be able to not look down and see that the purpose he has derived for himself is not sustaining? What happens to any of us who trick ourselves into believing that a finite purpose is worth it only to find that it is only the case so long as we are able to compartmentalize our purposeful thinking away from our eternal nature?
The frightening conclusion to the principle that life here on earth has no supernatural origins and thus no purpose is that should the entire human race give up right now and engage in a nuclear holocaust, or otherwise make Earth inhabitable for life, then it wouldn't make a difference in the grand scheme of things. The universe may never create life again and it wouldn't matter. Maybe it will, but that wouldn't matter either. If a supernova tree falls in the universal woods and no one is there to hear it, and all of that.
And, yet, it feels wrong to go blow up the Earth, doesn't it? The evolutionary biologist explains this by stating that the reason that humans are here right now is because of inherent survival mechanisms in our genes. We wouldn't be here if we didn't have an overwhelming urge to preserve our own race. But, how long can intelligent, conscious beings be satisfied and motivated by self- or other-preservation when science states that it doesn't really matter either way?
Interestingly, though, Mormonism gives an nod to the concept of self-derived purpose, though it isn't tied to self- or other-preservation. As mortals and as spiritual offspring of an Eternal Father in Heaven, we derive purpose encapsulated within His dominion. With eternal purpose in mind for His children, He places them into mortal bodies with the intent that a mortal experience is vital to our eternal progression. In Mormon theology, the ultimate destination for an individual is to become like God. And where does God derive His purpose from? He derives it from Himself, and if we are to become like Him, we will one day derive purpose solely from within ourselves just as He does.
The finite motivation of self- or other-preservation, though, is not present for beings who are eternal in nature. The motivation, instead, is self- or other-improvement or self- or other-progression. Only from an eternal standpoint can purpose be derived from within an individual; otherwise, the universe will just snuff it out in its unimaginable expanse. Only infinite circumstance can matter in infinite time and space.
Of course, science deals with the finite as nature itself is finite. Science itself cannot be considered a faulty system, especially as it has done so much for our society as a whole to this point. However, to consider a system that can only answer "how" questions and not "why" questions as complete is faulty. As Victor Frankl pointed out, people need a "why" to get through the "how", and unfortunately all atheism can offer is that the "why" must come from "within". If we are truly soulless, though, our within is finite and cannot possibly contain a "why" big enough to truly matter, even if that why is family, friends, or the mission to prove to the world that the why must come from within.
Do folks that declare themselves as atheists know what they are saying? I believe that what most people mean is that they are agnostic (they don't know) or even maybe apatheistic (they don't know and they don't really care). I believe that one of our greatest challenges in society over the next few decades will be growing apathy, so the latter one does bother me, but overall, I can empathize much better with these two than straight-up atheism. In fact, I believe that a healthy amount of agnosticism in everyone will go a long way towards establishing peace in the world. Wide-spread atheism, however, is a somber and dim future for the human family that will hinder our progress for lack of a "why" big enough to bear us through.
Theism, however ineffable you may perceive your higher power to be, gives us a "why" that is bigger than the finite universe and its infinitesimal human race. God is my reason, my purpose, and my motivation, and it is my goal to align myself with His will, because it is the only will that is big enough to matter. Theism is what carries me through the times in my life that seem too easy as well as the times that seem too hard. To me, atheism just says, "hey, your alone in this, now get over it and move on." That's just not big enough for me.