Thinking about swimming isn't much like actually getting in the water. Actually getting in the water can take your breath away.
You can learn new things at any time in your life if you're willing to be a beginner. If you actually learn to like being a beginner, the whole world opens up to you.
Real obstacles don't take you in circles. They can be overcome. Invented ones are like a maze.
Imaginary obstacles are insurmountable. Real ones aren't.
The defense force inside of us wants us to be cautious, to stay away from anything as intense as a new kind of action. Its job is to protect us, and it categorically avoids anything resembling danger. But it's often wrong.
Doing is a quantum leap from imagining.