Novelist John Irving wrote the screenplay based upon his novel because he felt it was important and didn’t want some hack to screw it up like most of the other adaptations of his work. Why? Because this story has a specific message. The obvious one would be about abortion.
Set in 1943, the movie begins at St. Cloud’s orphanage in Maine. Dr. Wilbur Larch (Michæl Caine) runs the place, and often delivers the unwanted children for their unwed mothers. He also, illegally, performs abortions. He loves the children he cares for, especially Homer Wells (Tobey Maguire). Homer, now 21, has rarely been outside the orphanage. He has been educated by Dr. Larch, and has the level of medical knowledge of a general family practitioner. Homer often delivers children, but he refuses to perform abortions.
What the film is really about are CHOICES: the need to make them, how they affect others, and actively dealing with the repercussions of your actions. When Homer encounters a couple near his own age, he hitches a ride to the coast and begins to experience life. He soon learns what the world is like without the comforts of a family or support system. More importantly, he learns what happens when you don’t make choices, don’t see how your actions affect others, and don’t deal with the repercussions of your actions.
The title refers to a list of rules posted in a buckhouse for migrant workers at an orchard where Homer stays for a while. The rules are both obvious and arbitrary, and are of little use in real life. What Irving is trying to say is that it’s nice and easy to tell a teenager not to have sex so they won’t get pregnant, but trouble happens anyway. When it does, you need to have some options, so that you at least have a choice. Don’t worry, Irving and Homer go through the trouble of explaining it to you.