REFLECTIONS about "Robinson Crusoe," the remote island of Masafuera, and the death of David Foster Wallace. In the South Pacific, five hundred miles off the coast of central Chile, is a forbiddingly vertical volcanic island, seven miles long and four miles wide, that is populated by millions of seabirds and thousands of fur seals but is devoid of people, except in the warmer months, when a handful of fishermen come out to catch lobsters.