Why does Diamond use historical anecdotes to support his argument at this point in the book, rather than some other kind of evidence, like statistics?
Pizarro defeated the Incan emperor Atahuallpa, just like the Maori defeated the Moriori in the previous chapter.
from ch. 3 of Guns, Germs, and Steel by Jared Diamond
In Chapter 3, Jared Diamond is trying to set up his argument about why Pizarro, for example, was able to defeat the Incan emperor. He is going to argue that Pizarro's victory came about because of the Spaniards' superior weapons and the germs that they carried with them.
He uses this anecdote, and a few others, to argue that it was the guns, germs, and steel that allowed the Europeans to win.
I think that he uses anecdotes here because there is not really any serious dispute on this point. Most people would agree that European technology and diseases helped them win. So it would be fairly pointless to show a bunch of statistics that prove that people with these thing win -- we already know that.
Instead, Diamond is trying to do two things:
- He wants to illustrate the importance of the things he mentions, and the anecdote is a good, interesting way of doing that.
- He wants to start us thinking about why the Europeans had these things and the Indians didn't.
This last thing is what he will spend the rest of the book on and he will start bringing in statistics when he gets to the points he actually needs to prove.
Both, historical anecdotes and statistical analysis are valid means for analysing and understanding historical events and causes that influenced them. Both types of tools are used by researchers like Diamond to understand the reality and to present it convincingly to others. Choice a technique in a particular situation will depend on many factors including nature of facts being studied and analysed, and availability of relevant data. Every researcher chooses appropriate methods bases on his or her assessment and judgement. Diamond does not clarify on his considerations of the choices he made. But I do believe that he is the best judge in this matter and must have made good choices. Only conjecture I can make about the preferring anecdotes over statistics is the limited availability of statistical data pertaining to the time and place Diamond is talking about.
Another important point is that absence of data on statistical analysis or any other rigorous research method in the book does not mean that these were not used by Diamond in his original research. Guns Germs and Steel is written for a wide section of people including laymen, and therefore, it is quite likely that descriptions of more rigorous analysis made - and perhaps, not of much interest to the average reader - were left out deliberately.