A poster to the thread ("Tom"), was implying that my observation of the purpose of life ("to better oneself through forming mutual beneficial relationships") was essentially the "life for life's sake" ideal. This was my response:

But isn't this just life for life's sake?

Well, there you've uncovered the paradox, as "life for life's sake" is a paradox in itself -- we live and die so that others may live, and other live and die so that we may live.

Whole religions are based on such concepts.

The paradox about the meaning and purpose of life could very well be that we exist to discover the meaning for ourselves.

It could be the ultimate goal of life to evolve to the point of discovering the meaning of it all.

Then again, it could be that we've always known it.

The lowest forms of life do not stop and question their existence. They do not say, "why bother?", give up and die.

That may seem a ridiculous concept, "Of course they don't! They aren't intelligent enough to."

Yet plants and animals live and evolve, change and adapt.

Something is giving them the drive to live.

Animals, plants, fungi, bacteria, viruses, etc, all have the will to live, to evolve, to carry on the struggle.

So here man is, a product of billions of years of evolution.

Yes, billions. We do not know for certain how old the oldest seeds of life are that seeded this planet, though we do know that there have been forms of life on this planet for over a billion and a half years.

We cannot say for certain that man is a somewhat direct descendant of some billion year old algae or not, but we do know that human DNA is pretty similar, surprising as that may be.

So after billions of years (and possibly several billion) of life striving, struggling and evolving, we get to a point where we have a form of life that can sit back, look to the stars and ask, "Why am I here? What am I supposed to do? What is the meaning and purpose of it all?"

Well, those single-celled organisms didn't seem to have to look too far to find a reason to live. Maybe we're missing something really simple and fundamental.

If you asked what was keeping them going... they'd probably point down to something smaller -- organelles, chromosomes, nucleosomes, DNA... and down smaller -- molecules, atoms, electrons, neutrons, protons, quantum particles...

If you could ask the smallest piece what was making it go... making it live... it would tell you "EVERYTHING!"

And there is the grand paradox. Those electrons zooming around the nucleus of an atom aren't just zipping around there for no reason. Something is making them go around, and it's all the other atoms, electrons, etc around them... and so on, and so on.

The grand paradox is that what makes the smallest piece of the universe go, is the whole universe.

There is no single piece of the universe that can exist on its own, and the universe cannot exist without all the smaller pieces.

The universe is all "one", and we are a part of it. We are all One.

So our purpose is little different than the smallest life forms, just on a larger scale.