Bearing in mind that I haven't read any of the material behind your link on the other thread, (and I find it exceedingly unlikely that I will ever put aside the time to do so) here is what is.
There is no purpose to life.
Once upon a yesteryear, on a timescale we can't begin to truly comprehend, the universe was.
If humans existed, we would have called it terrible, we would have called it beautiful. But humans weren't around, and those concepts did not yet exist. And so, for what we'd laugh and call an arbitrary amount of time, the first stars burned in the cold, hard night,
turning hydrogen into the denser elements.
The first supernova rent the serene monotony like cell phones rendered the fax machine obsolete,
but the stars didn't care. The stars still haven't realized the magnitude of that event, it marked the beginning of the process of planetary formation. Nebulae re-condensed, pulled into spheres by their gravity, but not all of the spheres were large enough to burn.
After an eternity, life evolved. It was so incredibly unlikely, but with such timescales involved, it was inevitable. And once life began to compete, the feedback cycle was closed, and evolution of life began to increase at an exponential pace.
Tribes of great apes fought and manipulated for social status, and suddenly in this world intelligence was valuable. Hominids evolved.
The human brain is an immense thing. Twenty percent of our metabolism goes to feeding it . . . which probably explains why we aren't so strong or fast as the other creatures. But that brain is worth it, neh? Because the human mind is the most complex thing in all of existence. And the most powerful.
There isn't an innate meaning to life. But I find that I like living, at least I like it better than the idea of not living. So I'ma gonna keep doing that.
And I really think that that is good enough. Good enough for anyone.
I came up with a very clever signature, as a matter of fact it's cleveritude was so clever that merely listening it would cause you to ascend to godhood. But then I forgot it, so instead you can listen to my gibbering inanities. I'm sorry.