"You're beautiful!" you say "I really want to swim with you. Can I, please?"
"Of course." replies the mermaid with a smile. "Just come into the water and you'll become like me. This pool has a submerged tunnel leading out."
You are about to step into the pool when you have doubts. You feel that sacrificing your legs may be too drastic a change. The mermaid senses your doubt. "Don't worry." she says "You'll be fine."
Gingerly you step into the water and..