In the book The Cay, why does the narrator tell Henrik a fib?

The narrator, Phillip, tells his friend Henrik a fib as a way of gently fighting back against his friend's slight arrogance. To be more specific, Henrik was annoying Phillip by acting like he had privileged information, so Phillip said something untrue in order to make it seem like he, too, knew a lot about what was going on.

This happens in Chapter 1, on page 12:

Henrik said, "My father told me there is nothing...

The narrator, Phillip, tells his friend Henrik a fib as a way of gently fighting back against his friend's slight arrogance. To be more specific, Henrik was annoying Phillip by acting like he had privileged information, so Phillip said something untrue in order to make it seem like he, too, knew a lot about what was going on.

This happens in Chapter 1, on page 12:

Henrik said, "My father told me there is nothing left of Aruba. They hit Sint Nicolaas, you know."

"Every lake tanker was sunk," I said. I didn't know if that were true or not, but Henrik had an irritating way of sounding official since his father was connected with the government.

Phillip's fib reveals that he's someone easily annoyed, and someone who doesn't like to be left out of the loop. The whole war seems exciting to him rather than frightening, and he's eager to know everything about which islands have been attacked, which ships have been torpedoed, and so on.

In a way, Phillip's reaction to his friend's statement shows how immature Phillip is; it shows us how he has a long way to go before he can understand why friends deserve respect, and why war should be perceived as something terrible rather than adventurous. The events of the novel will ensure that Phillip learns these lessons well.