[After 1900 told Max that he would leave the ship]
Max: Leave the ship, marry a nice woman, and have children. All those things in life which are not immense but are worth the effort.
1900: You'll come and visit me, Max, on land?
Max: Sure I will. That way you'll introduce me to the mother of your children, and invite me for Sunday dinner. I'll bring the dessert and a bottle of wine. You'll tell me that I shouldn't have bothered and while you're showing me around your house, shaped like a ship, your wife will be cooking a turkey. Then we'll sit at the table, I'll tell her she'an excellent cook, and she'll tell me that you often talk about me.
The Legend of 1900 is one of my favorite movies. Why did 1900 give up leaving the ship to get married to the one he loves? Before talking with Max, 1900 has made up his mind to find the girl on the land. It's Max's words changed his decision, I believe.
1900 prefers immense from experiences which are not infinite like the piano. To persuade him, Max described a detailed "happy marriage life" which are not immense but are worth the effort.
While Max was talking, 1900's blue eyes were clear and empty. He was attracted but soon he thought it's enough. The plain happiness as a husband and a father that you could imagine every detail couldn't satisfy him forever. Immerse life with piano in the ship is his final choice.