I used to think purpose in life was to experience the iconoclastic until I had my scizophreniform. Didn't really feel to have new experiences after that, it kinda screws your head up when you have them one after another for hours on end.
My philosophy right now is to love. And to love to me is this: to liberate, to console, and to yield.
And I think this entails that for the future, there will be peace, although there will be conflicts along the way. If you look at the whole of humanity through the lenses of history I think there is a definate purpose in life. We always strive for unity, as a whole. And to achieve this unity, we also strive for truth. There's a historical trend, a real narrative, which reflects this.
I also think that if you imagine humanity through the lenses of your own life, I think there is a definate purpose there too. I always thought what my worldview would be like if I were to be stranded on a deserted island by myself, for the entirity of my life. Would I go insane? Would I survive? What happens if I were to create a system in which all my worries for shelter and hunger were satisfied? What if I knew all the knowledge in understanding the beauties of nature- its dynamic and cyclic phenonemas? What if I understood reality and made peace with it? Then what? Does reality exist just so that we can experience and understand new things, one after another? To experience iconoclasm? No.. I don't think life's purpose is to experience the iconoclastic. I think the beauty of new knowledge dies with the passing of time. They are objective and eternal, after all, if they are to be discovered. It doesn't matter whether you think they're neat or not, they existed before you knew about them and were merely discovered.
I think ultimately we're meant to serve. I think it's the only vanguard against the human tendencies we have in ourselves. Knowledge brings sorrow, power brings corruption, love brings hatred. But I think with purpose- a universal, objective purpose- these things change. Knowledge brings joy. Power brings responsibility. Love brings unity. And so, I think it comes to this: to extert knowledge I think is to liberate. To extert power is to console. To love is to yield, to understand. And I think through all this, when thought in its totality, I think the purpose in life is to love, or something that is definately related to love. To liberate, console and yield. Something to do with that.
It's a bit of a loner/romantist approach, but.. I think you can get to the same conclusions with just philosophy, history, or sociology. The 'ultimate good', 'the ultimate trend', and the 'need to belong', respectively. etc etc. There are objective principles which guides these things. I don't think they are subjective or constructs of society, like things that arose because of necessity or something. I believe they exist in some form, objectively.