Most new ideas aren't. Someone, somehow, somewhere already thought up the essence of what you're thinking about.
Which is all the more reason to keep plugging away.
Accepting that someone else already had your idea is liberating, because it frees you up to learn. It moves the focus from what's going on in your head to what's going on in the world. Much of innovating is actually about stealing ideas from one context, connecting them to other ideas, and putting them to work in another. Where can you find analogous experiments or successes or failures that can inform your own work? Remember, before Facebook there was Friendster. And before the iPhone came the Newton. You can choose to live ignorance of what came before or what is happening in other parts of the world, or you can dive in and embrace all their hard-won lessons as your own.
Best of all, standing on the shoulders of giants is a free activity.
At the end of the day, if someone else has already had your idea, then the goal shifts from having ideas to making them real. Innovators ship, dreamers don't.
So what's keep you from making your idea real?
This is the eighth of 21 principles. Please give me your feedback and ideas.