Much is learnt from Santiago's life as a fisherman. In the first place, his humble background and simple needs are informative. Although he has gone out to sea for 84 days without a catch and neighbours in the community consider him luckless, `salas' in spite of earlier successes, he is not one to give up. This demonstrates his great tenacity that never-say-die spirit which lets him go out to sea again.
We learn that perseverance and tenacity help a lot, and that one must not give up easily when the odds go against us.
The boy, Manolin's relationship with Santiago is also a useful lesson to learn. He is an old man and he needs the boy just as much as the boy loves him. Manolin is able to read the old man's mind and determine his his needs. He provides him food, keeps him company and helps him carry his fishing gear to and from the skiff. Thus, the boy is sorely missed on that ill-fated expedition to catch the big fish. The old man cannot have felt lonelier and keeps on regretting the boy's absence: Here he provides another lesson which is the support a fisherman needs from others. This is clearly a cooperative enterprise and the old in in learns this lesson at great cost.
It is clear that no man is an island, We help one another. The old can be friends with the young and the young friends' with the old. 'This relationship is mutually beneficial.
Apart from the cooperation required, there are also the uncertainties at sea. The old man is unable to unable to predict how long it'll take him to catch a fish, nor 'where exactly to find it, in spite of some telltale signs. He does not also know how big' his catch will he and therefore cannot adequately prepare for all eventualities. This lack of adequate preparation and equipment is badly exposed when he is unable, finally, to ward off the attacking sharks which eat up his big catch. We also learn from the old man's respect for the marlin, that we should show respect to our rivals.
Finally the old man's attitude to the sea which he calls `la mar' when others call it 'el mar', indicates a certain love relationship. Thus; no matter how badly he has been treated by the sea, lie is prepared to go back again and again.