A simple life. The egg & bird represent one's soul. The story is about one's soul maturing into a full-grown bird which resembles a Phoenix. The Phoenix symbolizes rebirth. So when your body perishes, your soul leaves the body and will be reborned.
It's a brilliant conversation starter, I do believe I have used it before - not because Sherlock did, but because it's all I could think to say. I'm not exactly great at small talk…haha <-- pretty sure this is a sheldon cooper quote actually