About the Pearl the prince went out searching for...(spoiler
// spoiler alert//
I think the point of the movie is that money, successful Hollywood career, encounters with beautiful women, those things that the "envy of the rich and famous" TV shows promote are not the pearl the prince went out searching for.
So Rick mentions that he wasted thirty years of his life. then the last word he says is "begin".
Rick, Rick’s brother Barry, and Rick’s father all have big holes in their hearts. The youngest brother (or the middle one?) committed suicide years ago and they live with guilt, sadness, and anger inside them.
Rick’s brother Barry pours drugs into his hole but it never works. He blames his father for his brother’s suicide and pours anger on his father.
Rick pours alcohol and lust and things money can buy into his hole in the heart but they all come out of the other end and evaporate.
Rick is always aware of death and is reminded of the fact that he can die any time. It is shown in the earthquake scene and mugging scene.
Rick constantly pursues women and want them to fill the hole. Ex-wife Nancy was someone who was capable of giving love and care for people. It is shown in the scenes she cares for the homeless patients.
But Rick pushes her away. The reason is not given but it seems that he had anger in him and that he was incapable of loving her or himself. So they got divorced.
Elizabeth(Natalie Portman) says that love is rare and now that she found it she wants hang on to it. But she was already married to someone else and when she miscarries the baby whose father she is uncertain of, the love they had was gone in a blink. She must have had guilt but it is not expressed.
What the "pearl" is is left out for interpretation for viewers. It must be the most important thing in life.
I believe the movie leads us to the conclusion that the "pearl" is Love. It's not erotic love, it's the "love your enemy" Love. It is very hard to reach that goal as you have to forgive all, including one’s own self.
See how Rick's brother find it hard to forgive his father and has so much anger in him and it all leads him to his self-destructive, drug taking life?
Lose the unforgiveness and lose the anger completely and then the prince can find the pearl.