"Who knows what the tide might bring in..."

I love the movie Cast Away, with Tom Hanks. Every time I see it, I find fresh food for thought.
The sole survivor of the FedEX plane crash, Chuck Nolan is tossed around the raging ocean during the pitch-black night, on a life raft, and is finally washed onto an uninhabited island somewhere in the South Pacific. As he awakens at dawn on the beach, he is mostly stunned, and spends his first day on the island stumbling around, trying to make sense of the situation. As twilight of the first day settles, he stares thoughtfully out to sea at the pink and yellow breakers, tinted by the setting sun. By evening of the second day, he has found a source of liquid from the coconuts and the little puddles of rain water trapped in leaves. On the second night, as he's standing on the shore relieving himself, he sees a boat light way, way out on the horizon. It's just before dawn, but still dark. Agitated, he yells, jumps and runs along the shore screaming at the faraway light. The sun has crested by the time he grabs the life raft and charges out into the ocean with only a paddle. Rowing furiously, against the water current, he heads out to sea, but doesn't get far. The violent breakers hurl him into the air and smash him onto the ocean floor. Gasping and bleeding, he barely makes it back to shore, just in time to take cover in a hillside cave when a tropical rainstorm breaks.
Four years pass. He turns sun-ripened brown, loses thirty pounds, grows a long beard, talks to a volleyball that floated in with the other FedEx packages, and learns to survive on crabmeat and coconuts. Later, we learn, he almost commits suicide by hanging. Why remain living? He has no hope of ever getting off the island. However, he suddenly has a change of heart as he tests the strength of the hanging rope with a log. What if he fails in his suicide attempt and only injures himself? To be alone on an island and critically injured would be far worse than death---or life. Later he tells us, "At that moment, a warm feeling washed over me, and I knew that I HAD to stay alive, even in the face of no hope. I HAD to keep breathing in and breathing out."
A year later, the broken-off door of a port-a-potty washes in with the tide. What a treasure the old piece of junk turns out to be. In a moment of clarity, Chuck envisions the port-a-potty door as a combination sail and rudder that just might get a boat past the breakers. He builds a raft out of logs, binding them together with handmade rope from green tree bark, with the tape of VHS's from FedEx flotsam, and (with lovely symbolic possibilities) the rope that he almost used to commit suicide. As the weeks pass, Chuck carefully plans his exit, calculating the wind directions, the currents, the distance. When the seasonal wind direction changes and comes in from the West, he launches the boat. With his port-a-potty sail and rudder, he flies over the breakers and out to sea. Days later, an ocean-liner picks him up.
Returned once again to civilization, he says to his friend, "Against all possible logic, I'm sitting here in Memphis, talking to you, with ICE in my glass when I never had any hope of getting off that island." He learned from the experience that "every day the sun will rise---and who knows what the tide might bring in?"
The movie suggests that the Universe has its own sense of timing that is out of sync with human's. During Chuck's first attempt to escape the island, he was brutally shot down and thrown back, injured, onto the rocky shores. Yet four years later, when the time was "right," the very tool he needed came flowing gently in with the tide.
The literary possibilities abound in this movie. What about Chuck's rotten, infected tooth that he has to extract himself while on the island? He mutters, just before doing the deed and passing out from the pain, "I used to avoid dentists and now I'd give ANYTHING to have one here on this island!" Only to get home four years later and discover that Kelly has married a dentist---the same one who performed a root canal on Chuck five years earlier. But that discussion is for another time!