Within the context of the novel, Santiago's mistakes aren't mistakes as such, but lessons that he needs to learn to achieve his Personal Legend.
Arguably, the only true mistake he makes is at the very beginning of his travels when he entrusts his money to the Arab man in the bar on the flimsy basis that the man speaks Spanish and dresses in Western-type clothes.
The new arrival was a young man in Western dress, but the colour of his skin suggested he was from this city. He was about the same age and height as the boy.
His distrust of the other people in the bar, who act and talk more like locals, is highlighted when he comments on their smoking habits,
"A practice of infidels," he said to himself. . . . The boy felt ill and terribly alone. The infidels had an evil look about them.
The loss of his money, however, liberates him. Now he has to trust the so-called infidels in order to survive. This quickly leads to him getting a job at the crystal shop.
After this, his only other mistakes, if...
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