My dad taught me to swim at Whipples Dam State Park in the boondocks of Pennsylvania. Swimming is a skill every child should learn. I really enjoy watching the little-kid swim lessons going on at the YMCA when I am lap-swimming.
But I suspect Ms. Walls was talking about more than actual swimming skills. We can't hang on to safety forever... At some point we have to let go, get out into the world, and explore, experiment and adventure. We can see the drive in an infant as he gradually learns to roll over, hold the head up, crawl, stand, toddle and run. Our whole reason for being here is to "let go of the side." One is never too old to do that. There are considerably more "life preservers" out there than we can imagine.