In chatting to many people I have been able to help them identify their basic purpose. It has always been a specialization of the desire to help.
I think the problem is that we are not taught to look for it, to recognize and pursue it. In many cases we are dissuaded from it – “You can’t make enough money doing that!”
If you would like some ideas on how to identify your basic purpose, here’s a blog post I wrote to help you:
How To Work Out Your Basic Purpose In Life