Rules
It's late here where I am, and I'm almost inclined to try to think up a silly answer, but I won't.
Instead, I'd like to simplify your question with a quote of my own from over 20 years ago...
"An age old question is 'What's the meaning of life?'
But the better question should be 'What's the motivation of life?'"
If the question lingers so much, it never hurts to ask those who created us what the meaning of it all is. Either our parents (or grandparents like in my case, or our ancestors), as our most rightful authorities, are going to explain to us what our purpose is, or we ourselves are going to do that ourselves.
Well, it's six in the morning and I'm up, so I guess it's working.
The word you might be looking for is "innatism". The self-informative parts of mine work. The self-feeling parts, on the other hand...