silently. Most parents, doubtless, are too busy to spare time to educate their sons and daughters by reading to them, and as the children grow older they find their hours too crowded to devote any of them simply to listening. “What is the use” they would say, if asked. “Tastes differ, and we can read what we want in a fraction of the time that would be consumed if we had to sit still and hear it.3 However, as the salon and family circle faded, magazine clubs and book clubs took off into the twentieth century. Another cultural factor altering the spread of narratives has been an international movement toward providing mentors for young people, with roots back to the Big Brothers (now Big Brothers and Big Sisters) movement starting in 1904, and later diversifying into an epidemic of sorts since around 1980. Having regular communications with successful or socially committed people helps a young person gain a sense of identity in the mentor’s life stories, or in stories that the mentor tells of others in the same circle.4 Mentoring groups are especially effective for women and minorities who may have felt little ownership of such stories.5 Two new phrases, influencer marketing (since 2015) and social media marketing (since 2009), have been gaining popularity. Marketing firms, notably shareablee. com and hawkemedia. com, offer influencer marketing, systematically finding influential people who allow marketing to them or with them via social media. Such sites should increase contagion rates for promoted stories and ideas. Even as information technology is affecting the transmission of economic narratives that affect the human mind, it could conceivably go further and replace some of the ultimate decision-making process that individuals use. For example, we already have robo-advisers that offer advice on how much to consume and save and how much to put into the stock market versus other investments. The first robo-adviser was launched in 1996 with William Sharpe’s Financial Engines. Since then, automated advisers such as Schwab Intelligent Portfolios, Betterment, and Wealthfront have proliferated. There are other efforts to automate economic decisions too, such as target date funds, first attracting interest around 2007, that automatically rebalance a long-term investor’s portfolio based on a target retirement date. There are many other applications of algorithmic trading. Nonetheless, today, people write the programs and make the ultimate foundational decisions. Someday people may defer massively to machines for life decisions, in which case economic processes may be fundamentally altered. But that day appears likely still to be far-off. Modeling technology’s effects on communications will be easier to trace when there is better science behind the spread of economic narratives. Already, our models show that it is not easy to predict these narratives and their effects. For example, the epidemic’s ultimate size may not change when an increase in the contagion parameter is matched by a corresponding change in the recovery parameter. Rather, the epidemic will just happen faster. We must integrate formal models of contagion into economic models to begin to understand the impact of such technology. The Future of Research in Narrative Economics It is very important, if we are ever to have a substantial understanding of the kinds of big economic events that have surprised us so often in the past, that we have some scientific methods of studying the narrative element of these, even if the science is not complete and still involves some human judgment. Otherwise the field will be left to prognosticators or prophets who give the whole enterprise a bad name. Economic research has not emphasized the stories that people tell to one another and to themselves about their economic lives. The research misses any discernible meaning that appears in the form of narratives. By missing the popular narratives, it also misses possibly valid explanations of major economic changes. If one searches newspapers of the twentieth century for contemporary explanations of recessions as they begin, one finds that most talk concerns leading indicators rather than ultimate causes. For example, economists tend to bring up central bank policy, or confidence indexes, or the level of unsold inventories. But if asked what caused the changes in these leading indicators, they are typically silent. It is usually changing narratives that account for these changes, but there is no professional consensus regarding the most impactful narratives through time. Economists are reluctant to bring up popular narratives that they have heard that seem important and relevant to forecasts, since their only source about the narratives is hearsay, friends’ or neighbors’ talk. They usually have no way of knowing whether similar narratives were extant in past economic events. So, in their analyses, they do not mention changing narratives at all, as if they did not exist. We can already today learn something about popular economic narratives by counting words and phrases in the digitized texts that are available, but there has not been enough organized research to measure the strength of the competing narratives that combine and recombine over time to cause major economic events. Artificial intelligence can help with this—especially with unstructured data. The perennial narratives described in part III of this book are works in progress, not final and exhaustive quantifications of all truly important narratives. Research on narrative economics has already begun and surely will continue,