What happens when you step outside everything that seems rational and safe? This isn't about doing something foolish, but about moving outside your comfort zone to see where it takes you. Trying something new, learning something new, talking to someone new.
When we were kids everything was new. Children try things because they're exciting and new and sometimes a little scary.
Remember when you learned to ride a bike? When you got that first bicycle you couldn't wait to get on and try it out. Excitement, butterflies, and maybe a little fear in the pit of your stomach as you climbed on for the first time. A few tries, a few falls, maybe some tears, and the feeling that this wasn't such a good idea after all. With a little encouragement, Mom or Dad steadied the bike as you climbed back on, and started running behind, holding on until they couldn't keep up. The bike wobbles a moment, and you look back and realize they had let go and you were riding! You keep pedaling, pedaling, wind in your face and a feeling of accomplishment and freedom in your heart.
That's the kind of fearlessness that is never regretted.