Interventions to Do Real-World Good: Generalization and Persistence

In his 1955 address to the National Academy of Sciences, Richard Feynman delineated three key ways in which he saw science as having value (Feynman, 1955). One of these ways was the simple “intellectual enjoyment which some people get from reading and learning and thinking” (p. 13). For many scientists, there is intrinsic value in simply coming to understand how things work. They feel a certain joy when aspects of the world that previously seemed completely mysterious or idiosyncratic become less so. And this is true regardless of how the knowledge is eventually put to use. Yet it is inarguably the case that those eventual uses represent the greatest long-term value of science to our broader society. As Feynman said in discussing this second way that science has value, science is important because it “enables us to do all kinds of things and to make all kinds of things” (p. 13). In other words, increasing scientific understanding of a domain provides for the increasing possibility that we can apply some degree of control in the domain. Science offers the promise that we can manipulate, and thus potentially master, our circumstances. This core notion certainly permeates the behavioral sciences. Throughout the literature, one consistently sees manifestations of the idea that if we come to truly understand the mechanics by which human abilities, skills, knowledge, and other life outcomes emerge, then we might be able to purposefully intervene so as to alter those outcomes for the better. And although we are absolutely (very, very) far from mastering our circumstances in this domain, there are at least many reasons to be hopeful that such goals will eventually be within our reach. Such reasons for optimism include, for example, promising and ever-growing bodies of research on behavioral interventions meant to increase mental health and well-being (Creswell, 2017; Davidson & Dahl, 2018), interventions meant to decrease bias and prejudicial actions (Lemmer & Wager, 2015; Paluck & Green, 2009), interventions meant to increase cognitive and perceptual functioning (Au et al., 2015; Bediou et al., 2018; Deveau, Jaeggi, Zordan, Phung, & Seitz, 2014), and interventions in the educational sphere, such as those to promote reading abilities (Bus & van IJzendoorn, 1999; Kim & Quinn, 2013). Yet in considering previous work, as well as in evaluating the potential of future work, it is critical to recognize that in most cases of human behavior, truly “doing good” necessitates that the effects of interventions meet at least two key criteria: (a) The impact of the given intervention needs to generalize reasonably broadly and (b) the impact of the given intervention needs to be enduring. If the impact of an intervention is exceedingly narrow, or if the positive impact lasts for only a short period of time, this will obviously reduce the real-world good that will be realized from the intervention. It is therefore somewhat unfortunate that the field of human learning has consistently run into significant obstacles on both key fronts—generalization and persistence.