Different people have different ways of responding to the thought that they are very lucky to be alive. For me, it seems to suggest great responsibility to make the most of it. I mean, I am extremely lucky to be here, that odds against you are being here is far greater than the odds against you are winning lottery. So be thankful and spend your time, your brief time, under the sun, looking at around and rejoicing and wondering and being fascinated and trying to understand everything about the Universe in which you are so fortunate to be born.
This is so close to what I have been thinking (the phrases I have highlighted in blue are particularly.). Although, I do not think life is only full of joy. Depending on our luck, we may have agonising diseases or tragic memories. I am sorry for those people, but for most of us, the joy of being a live is greater than not being born. I have not read the book but I heard that Tolstoy wrote in a book, that life is like feeling the small happiness tasting the sweet sweet dew while he is hanging on a tree trunk in a well, where a lion is at the top and crocodiles on the bottom of it (or a similar story, I do not remember exactly).
Everything I think, I remember is the acts of my brain, the physical organ inside my head. I do not think there is another supernatural part of I that can think independently of the brain. My brain is made up of ordinary materials such as carbons, hydrogens, oxygens and so on. Those atoms could easily have been something else, like a rock or some gas. But, by an indescribably small chance, billions and billions of those atoms happen to flock together at this moment forming my brain which is, basically, my identity. If I am the brain, I am also the atoms that comprise the brain. So, I could have been just mindless atoms wandering the Universe. But here I am, recognising myself, looking around myself, thinking about the Universe.
The fact that I can think and feel is great enough to be the meaning of my life. But it does not stop there. I can also do things. I have, as a human being, the ability to decide how to spend my own life. Some life forms are rather similar to be atoms. They are mindless and all they do is just multiplying. I am very lucky to specifically to be a human. I know life is extremely short compared to the history of the Universe. I want to experience as many things as I can in my short life. I want to discover and understand why the Universe is, and things are like what they are.
I get very upset when Christians keep saying that there is no meaning or purpose of life if there is no God. Why is it so? I set my own purpose of life and I am satisfied with it, who are they to decide that my life is meaningless? If I think my life is meaningful and you think my life meaningless, it just means that my life is meaningless to you or to your God. Sorry Christians, it is what is called tautology. If I think my life is meaningful, my life is meaningful to me, period. There is no way you can make my life meaningless by introducing your God.
As far as I know, Christians usually say that the purpose of life is to glorifying, worshipping, and subjecting to God. Even if your God does exist and he is a good being, that thought horrifies me. Endless worshipping, praising and worshipping... to the end of time. What a long, boring and painful life will it be. And if such God does not exist, what a waste of time, when life is so short! If there is a creator who made human beings, why would the creator want us to spend our short time worshipping himself? Would you? I would not. Personally, I am thinking about writing a computer simulation program for evolution. The purpose? I just want to see how things can evolve. I would never hope that the objects in the simulation someday evolve to worship me as their creator. It is so moronic that the most great being in the Universe wants some reputation or some recognition from puny human beings, like a child who wants some recognition from his teacher.
If there is God, and God dictates the way I shall live and I shall behave, then my life will be meaningless and boring. It will be like an actor who reads things that writers have written for him. So, no thanks, I want to be a writer, not an actor.