A guy I know told me how tough it is for him to accept that his house is worth less than what he paid for it. It hurts him to write that fat mortgage check each month. His wife just had another baby, and his future with his current employer appears dim. “I’m almost underwater,” he said. “I don’t know how long I can stay afloat.”

For starters, how about 133 days? That’s how long Chinese merchant sailor Poon Lim survived on a makeshift raft after his British-flagged vessel, the SS Ben Lomond, was torpedoed in the South Atlantic during World War II.

Poon Lim’s story is one of the first survival-adventure tales I recall reading—way back in elementary school—and it was so incredible, I’ve never forgotten it.

With his fellow sailors down in Davy Jones’s Locker, Lim clambered aboard a small raft stocked with emergency tins of biscuits and drinking water. He figured he’d have enough to hold out until he was rescued. But there would be no government bailout for Lim. A month passed with no sign of rescue, and Lim—a ship’s steward with no survival training—knew it was up to him to find a way to stay alive.

Lim used what was at hand, fashioning a crude knife from an empty rations tin and jury-rigging the canvas cover of his life vest to collect rainwater. Nails from the raft became fish hooks baited with the last of his biscuits. With patience his ally, Lim managed to pull a struggling fish from the dark blue depths. After devouring the cold, tasty flesh, Lim let the fish remains bake in the sun where they lured in seagulls eager for a free meal. Lim managed to grab and subdue the gulls and add them to the menu. (I still remember how the raw gulls were described as having an “oily taste.”)

When faced with a dire predicament the mind often dwells on dark thoughts. But Lim knew he had to keep his head occupied in a positive way with a disciplined daily plan. He maintained his raft, fashioned tools, and fished. He celebrated each little victory over the elements, and tracked the weeks at sea by tying knots on a rope.

Several times while adrift Lim sprang to his feet and thought he was saved. A ship passed by but never acknowledged his desperate cries for help. Another day a squadron of planes buzzed overhead but never spotted his tiny raft against the expanse of the Atlantic. Then there was the time when a U-boat surfaced a stones-throw away, but the crew paid him no mind. His heart sank yet again, however, Lim knew that as long as he was alive, there was hope.

Finally after over four months at sea, Lim was rescued by fishermen off the Brazilian coast. Hailed as a hero, the castaway was honored by the King of England, and eventually emigrated to the United States. Later, the Royal Navy created survival-training materials based on Lim’s tactics.

Like my friend with his housing and job woes, you can’t control a dashed career prospect or tough financial blow. But like Poon Lim, you can re-evaluate your own skills and prospects and take action to make sure you survive. As Lim knew, there’s always an opportunity somewhere on the horizon.