In a research experiment, a marine biologist placed a shark into a large holding tank and then released several small bait fish into the tank. The shark quickly swam around the tank, attacked and ate the smaller fish.

The marine biologist then inserted a strong piece of clear plexiglass into the tank, with the shark on one side and a new set of bait fish on the other. The shark attacked, slamming into the plexiglass divider over and over. The fish swam around unharmed in their section. After about an hour, the shark gave up, according to this story from Bits & Pieces.

Over the next few weeks, the shark made fewer attempts to attack the fish, until it stopped attacking altogether. When the marine biologist removed the divider, the shark didn't attack. It believed a barrier existed between it and the bait fish, so the fish swam wherever they wished, free from harm.

I love shark stories; is it any wonder why? But how many imaginary barriers do you see separating you from what you really want?

Many of us create barriers for a variety of reasons. Maybe we were trained a certain way and need to reprogram ourselves. We don't think we have options. We don't want to take chances or rock the boat. Or it could be that we simply don't want to do something, so we create doubt.

If we try something and fail, is that a reason not to try it again later? Things change. We change. That's no excuse to give up on something.

I wrote a column years ago about the late Randy Pausch, a professor at Carnegie Mellon University who learned he had pancreatic cancer. He gave a final upbeat speech, eventually viewed by millions, titled "The Last Lecture."

In it he said: "The brick walls are there for a reason. The brick walls are not there to keep us out. The brick walls are there to give us a chance to show how bad we want something. Because the brick walls are there to stop the people who don't want it bad enough. They're there to stop the other people."

But brick walls get knocked down every day. When you know that what you want is on the other side, and you want it more than you want anything else, you go looking for a sledgehammer.

I think of the challenging times when I was starting my company, or when the envelope business seemed to be on the brink of extinction, or when a civic project I was heading up hit a roadblock. It would have been easier to give up. But then I would have to live with my decision to quit rather than persevere. Could I overcome that disappointment?

In the wise words of Sir Edmund Hillary, who, along with Sherpa Tenzing Norgay, was the first person confirmed to reach the summit of Mount Everest: "It is not the mountains we conquer, but ourselves."

So who says that you can't accomplish your goals? Who says that you're not tougher, better, smarter, harder-working and more able than your competition? It doesn't matter if they say you can't do it. The only thing that matters is if you say you can't do it. As we all know, if we believe in ourselves, there's little we can't accomplish.

The shark from my opening story would have been wiser had it heeded the words of Oprah Winfrey, whose career had plenty of bumps as she started in television: "Do the one thing you think you cannot do. Fail at it. Try again. Do better the second time. The only people who never tumble are those who never mount the high wire. This is your moment. Own it."

Surviving a setback is more tolerable if you step back and review your goal. Get some perspective on the direction to take when you recover from this stumble.

When I have doubts, I always remember the words of Thomas Edison, perhaps the greatest American inventor, who said, "I have not failed. I've just found 10,000 ways that won't work."

Mackay's Moral: Build bridges, not barriers.

Contact Harvey Mackay at 612-378-6202 or