London, England (CNN) -- Not many people would see quadriplegia as a gift. But then, not many people are Paul Callahan.
As a 21-year-old Harvard University student, Paul's life was full of possibility. An undergraduate studying business at one of the best universities in the world, there was a lot to look forward to for the young man from Massachusetts.
Then a freak accident changed everything. Paul slipped on a wet floor, breaking his neck and rendering him paralyzed from the chest down. He retained the use of his arms, but not his hands.
Callahan spent the next five years traveling to rehabilitation centers across the United States in search of a way to walk again. When a doctor finally suggested it was time to concentrate on living instead of walking, Paul did exactly that.
Almost 30 years later, the 55-year-old father of two is now set to represent the United States in sailing at the Paralympics.
"It's an evolutionary process where you transition from one life to the other," Paul told CNN.
"I never gave up moving forward. You can define that as walking or being a contributing member of society. At 26 I chose the later."
Next week Paul and his two team mates -- both amputees -- will take to a 24-foot boat for the three-person sailing event at the Paralympics.
Skipper Paul drives the boat by wearing rollerblading gloves on his hands, attached to bicycle pedals. The pedals are in turn linked to a pulley system that steers the vessel.
This will be Paul's second Paralympics, after his debut at Sydney in 2000. The U.S. team failed to win a medal, but as Paul admits he was still fresh to the sport.
With a fifth place in the Disabled Sailing World Championships in Weymouth last year, this time gold is on the cards, he insists.
It would be an incredible achievement in a life already marked by success. Paul returned to Harvard in 1983, becoming the first quadriplegic to graduate from the university.
He then went on to work at Goldman Sachs as an asset manager for 15 years.
"Everyone is quite capable of doing much more than they think they can," Paul said.
"Once they realize that fact, then the world becomes their oyster."
Sail to Prevail
It was a chance sailing trip in 1995 that sparked Paul's love for the sport -- and a new venture that would help thousands of disabled children.
"I got on a sailboat and looked back at my empty wheelchair on the dock," Paul said.
"It was the first time in 15 years I was able to do something on my own. It was an incredible moment."
So inspiring was the experience, Callahan left his Wall Street job and took over Sail to Prevail -- a non-profit organization that teaches disabled children to sail.
From starting with eight children a year, the charity, based in Newport, Rhode Island, now helps around 1,000 youngsters annually.
Their disabilities vary from spinal cord injuries to autism, and Paul says when he races for gold next month, it'll be for them.
"When we get on the starting line against 14 other countries, I want to win a gold medal just as much as they do -- but I've got an additional motivation," he said.
"The better my team does, the more powerful impact it will have for Sail to Prevail."
It is perhaps a testament to Paul's mental strength that he views his disability as a special opportunity in life.
"I've been given an extraordinary gift where I can affect people's lives in ways other people can't. So I see it as a responsibility," he said.
There have been some dark moments Paul admits. But with his wife, Alisa, 9-year-old twin sons and the Paralympics on the horizon, what's the point in dwelling on that instant he slipped on a wet floor?
"I've been very fortunate," he said, adding: "You've only got a limited amount of time in life. So you may as well choose to put that towards positive effort, rather than squandering it on the negative."