It is poetry. Given the context, it is a sentence which stresses the importance of language, to reflect and language and to use it properly. Language has grave consequences.
Thank you for the kind welcome. Will read.
Could you find examples of societies who act differently? Yes. Can culture twist/avoid Kin altruism? If so, I can also invent an evolutionary story to fit that culture just as easily. Does EP explain all of these different cultures via natural selection? I did not find any so far. Evolutionary biology always seems to "explain" a narrow provincial behavior and always in postdictions.
What is satisfying? Something accurate enough avoiding ambiguity, taking in account of all of the facts & and provoing an accurate account of the actual cause of behavior (different cultures, sociology, different possible causes - i.e. actually proving it's bio-psy-evolutionary roots that drive such -detailed behaviors- & not local cultures). I could understand wider impulses as relatively probable & testable, but "sacrifice themselves for three brothers but not one", that is one huge kind of a detalied leap. Since when by the way observation is enough? You need to determine the actual cause from all the other possible ones.
I find this to be a major obstacle for the success of this enterprise as a science.
"It is startling to realize how much unbelief is necessary to make belief possible. What we know as blind faith is sustained by innumerable unbeliefs."