The question is whether or not "ideas" exist as a 1-only development within a single human mind, or if they`re a "wave" of information, picked up by multiple minds "attuned" to that particular idea.
Throughout history we hear about big ideas that move through a culture or society. Tracking them down, we find almost always that there were several people with almost the same thing, exactly the same thing, or a closely related idea, working at the same time.
The telephone is an excellent example, where it was only a matter of hours difference between the two patents hitting the Patent Office, both for the same instrument.
My own thinking is that when you get an idea, you have to decide how important is it to your overall life plan and scheme of things. "Idea people" tend to have many ideas, but all of us have to specialize---particularly in today`s world.
As such, and again in my own opinion, if an idea looks pretty good to me, my first analysis refers to what I would want to do about it. But one of the immediately important variables is to assume that the same idea is "hitting" a whole population of other minds, right now, right at the same time, all over the world.
I believe the next step is to make an informed analysis about competition. "How" and "why" would someone else get involved in the idea. If it`s easily possible for anyone else (with the same idea) to bring it to market, then there`s a time crunch. If the idea rests on a rare or extremely complex set of personal skills, there`s less of a rush.
Following the competition assessment, it seems to me that the "components" of the idea come into play. In the GPS phone idea, who controls the phones, and who controls the GPS capability? Obviously, no single person controls the entire satellite system and computer network involved in global-positioning satellites.
Therefore, the likelihood of people with huge amounts of money, having the same idea, and being capable of competing would make the idea very hard to manage.
It`s a really interesting problem for any entrepreneur, and for anyone who comes up with idea on a routine basis.