 Once we adopt the perspective of argumentation as a communicative practice, the question of the influence of cultural factors on argumentative practices naturally arises. Is there significant variability in how people engage in argumentation depending on their sociocultural backgrounds? Or is argumentation largely the same phenomenon across different cultures? Actually, we may even ask ourselves whether argumentation in fact occurs in all human cultures, or whether it is the product of specific, contingent background conditions, thus not being a human universal. For comparison: it had long been assumed that practices of counting were present in all human cultures, even if with different degrees of complexity. But in recent decades it has been shown that some cultures do not engage systematically in practices of counting and basic arithmetic at all, such as the Pirahã in the Amazon (Gordon 2004; see entry on  culture and cognitive science).  By analogy, it seems that the purported universality of argumentative practices should not be taken for granted, but rather be treated as a legitimate empirical question. (Incidentally, there is some anecdotal evidence that the Pirahã themselves engage in argumentative exchanges [Everett 2008], but to date their argumentative skills have not been investigated systematically, as is the case with their numerical skills.)