What answer does Diamond propose to Yali's question in the prologue of Guns, Germs, and Steel?

Theto 's
does not offer a detailed answer to Yali's question but instead introduces
the issues involved in trying to discover an answer and introduces the material that will be
covered in the rest of the work.

First, Diamond agrees with the assumption
inherent in the question, namely that Europeans do, in fact, have more "cargo"
(wealth, material goods, advanced technology) than the natives of Papua New Guinea. Next, he
points out that the answer does not lie in the character of the people themselves. He states
that people living in less technologically advanced areas are just as intelligent and
hardworking as Europeans. Because of this, he concludes that environmental factors must have led
to the disparity in quantities of "cargo" and tells readers that the rest of the book
will be intended to analyze the ultimate causes for these differences in detail.