Via Tyler Cowen:
We hypothesized that the increased role of science, education, and technology in Western society in the relatively recent past should have been accompanied by detectable cognitive changes and, more specifically, by an increased focus on causality. To test this hypothesis, we measured the amount of causal language in historical texts in five corpora. In four of the five corpora, we found an overall increase in causal language. We also found different trends for the 19th and 20th centuries. Although we detected an increase in causal language during the 20th century in all five corpora, the results for the 19th century were less consistent. The three Google Books corpora revealed a reliable decrease, whereas the two periodicals showed a nonreliable positive trend. The decreasing trend in books might be a statistical artifact attributable to the relatively small number of available texts for earlier periods, but it also might be related to the early popularization of nonscientific books, when authors started writing books for the broader masses. The overall trend, however, strongly supported our prediction for an increase in causal language.
If we accept that the number of causal words in text corpora from a particular cultural context can be used as a proxy measure for the number or salience of causal inferences that people make, then our results have two important theoretical implications. First, they add to the body of work that links cognitive processing to cultural and societal factors (Vygotsky, 1980). As we suggested earlier, increased attention to causality is not surprising given the increasing role of formal schooling, popular science, and everyday technology. The second implication concerns the origin of current cross-cultural differences. Similar to the changes observed by Greenfield (2013), the changes we observed in these studies have occurred over a relatively short period of time, which suggests that researchers should focus not only on ancient history but also on more recent historical processes within cultures.