Whenever someone has the inkling to make a career change or is kicking around a new idea, I tell them about the Sky Earth Theory. It goes like this: Blue-sky it, then engineer it back to Earth.

I learned it years ago from a man named H.B. Gelatt. He didn't call it the Sky Earth Theory, I do. But he offered up some of the best advice you'll ever get when you're in that crucial initial phase of entertaining a new business idea, direction or career change. Ignore the advice and you'll probably never get to phase two — making it actually happen.

Most people ignore it. Instead of allowing themselves to contemplate "what if I could ... ," they seem incapable of stopping themselves from conjuring up all the reasons why they can't. It would be delusional to do otherwise, they tell themselves.

"Why I'd love to start my own business ... work for a nonprofit ... help children ... be a nurse ... but I can't. It's not realistic," they say. I've heard it almost as many times as I've heard someone tell me they want to make a career change — which is hundreds of times.

There was the lifelong teacher who wanted a new career involving travel but didn't think anyone would pay her for that. She didn't know what "that" was, but was certain she couldn't have it. The superstar sales guy who wanted to help people deal with personal problems by working as a counselor but was convinced he didn't have the time or money to go back to school. The young accountant who wanted to do anything — anything — but deal with numbers, but couldn't because "my father would be upset."

If, though, you are someone who would rather not endure a career in purgatory and are open to the possibility of change even with all odds against it, the Sky Earth Theory is for you. First, you blue-sky it. Dream a bit. Then you can get practical and engineer your idea back to Earth.

This is where you look at your life and say, what would it take to make this happen? Would I need to go back to school and if so, how could I swing that? Even without school, would it cost money? How much risk is involved, what is that and how can I minimize it? Who should I talk to to get the support I need? How will I need to change my life to make this happen? Am I willing to do that?

Your idea may not work. Or it might. But you'll never know if you don't start with the blue sky part then figure out if it's doable.

Everything starts with a notion. To get the ball rolling it becomes a declaration, which then has the potential to become reality.

This month we are celebrating one of those notions-turned-declarations that became reality. We're noting with great pride the 40-year anniversary of the first human to set foot on the moon. That happened because eight years prior, President John F. Kennedy made this declaration in his May 25, 1961, speech to Congress: "I believe that this nation should commit itself to achieving this goal, before this decade is out, of landing a man on the moon and returning him safely to the Earth."

Your new career goal may not be as lofty as sending a man to the moon. But it begins with your willingness to entertain a notion. You have to start somewhere. What better place than the sky?