特別編です
2021年8月開催の日本社会心理学会第62回大会で招待講演をお願いしたBeth Morilngさん（デラウェア大学）とJoshua Tyburさん（アムステルダム自由大学）からも、「社会心理学と社会」について回答をいただきました。特別編として公開します。（他にも、講演内容にかんする質問・コメントに回答いただいております。こちらからご覧下さい。）

Beth Morlingさん（デラウェア大学）

Morilngさんには "Teaching social psychology after the replication crisis" というテーマで講演していただきました。それも踏まえつつ、少しテーマがずれますが、「新型コロナ」ポスターセッションと同様の質問を投げさせていただきました。

Question: To what extent do you think it is possible or appropriate to make specific social/policy recommendations based on the current state of social psychology? In response to the Covid-19 pandemic, on the one hand, there is a position that we should actively disseminate social science findings for policymaking (Van Bavel et al., 2020). On the other hand, there is a position that findings from social science are not yet robust, reliable, or generalizable enough to make specific recommendations to society (IJzerman et al., 2020). What is your current impression of the situation?

Reply
Yes, besides the concerns with replicability, I suspect that another limitation of social psychology studies is that they tend to be run on convenience samples, rather than random samples. We have long prioritized internal over external validity. This means that studies run on American college students may not be very informative for policy in Japan. Persuasion studies run on consumer topics may not be informative for Covid policy. Studies on 18 year olds may not help us intervene with senior citizens. (There's nothing inherently wrong with our field theory-testing and focusing on internal validity over external validity (see Mook, 1983). But we should realize that theory-testing is only the first step--in order to apply our work we need to take the next steps and see how well our studies work in other samples and situations.) Therefore, when it comes to the pandemic, between the replication issue and the generalizability issue, maybe we should stay quiet!

On the other hand, that seems a very dark conclusion. I think we as social psychologists do have more to offer than just...nothing. Maybe the most conservative scientific approach is to develop theory-based interventions, and then propose ways to implement them while simultaneously testing them. Researchers (like Milkman, above)* have found some really creative solutions...they come up with social psychological theory-based interventions, and then use Big Data sets and large platforms (like Facebook or mass text-messages) to test them.

In my view, social psychologists contribute not just our theories to the world, but also our scientific reasoning and experimental methods. Maybe not all of our potential interventions have been replicated, and maybe some of them came from non-generalizable studies. But at least we know how to test these interventions. We could use those skills to make the world better. If we stay quiet, that means that people might end up using "common sense" interventions that they *think* will work (not guided by theory)--and worse, they might just implement policies without testing anything.

One of my current favorite examples of "common sense" without testing comes from medicine--for decades in the U.S., surgeons treated breast cancer with radical "Halsted" mastectomy--a major surgery that removes muscle tissue, lymph nodes, and even rib bones. U.S. surgeons were fully positive this was the right approach. After all, cancer is scary and you want to be sure you get it all in case it has spread (that's just "common sense"). Surgeons were so confident in this procedure, that they never even compared it to any other procedure. Their confidence even prevented anybody from challenging or testing them. Finally, in the 1970s in the U.S., scientists started conducting an RCT, comparing radical mastectomy to less invasive procedures--and they found that there was no difference in 10- or 25-year survival rates (Fisher et al., 2002 DOI: 10.1056/NEJMoa020128).

This is an important story to remember, I think. Social psychologists are trained not just in theories and "facts" but also in the scientific mindset--we can help our policymakers by helping them both design and *test* interventions.

* 「上記のMilkman」とあるのは、他の質問への回答の中で触れているためです。

Joshua Tyburさん（アムステルダム自由大学）

Tyburさんには "The psychology of infectious disease – before, during, and after COVID-19" と題して、彼の専門である行動免疫システム理論の観点も踏まえつつ、心理学とCovid-19パンデミックの関わりについて講演していただきました。Tyburさんには、そうした彼の専門との関連も踏まえて質問させていただきました。

Question: This is a rather big question. To what extent do you think it is possible or appropriate to make specific policy recommendations based on the current state of evolutionary psychology and social psychology? In response to the Covid-19 pandemic, on the one hand, there is a position that we should actively disseminate social science findings for policymaking (Van Bavel et al., 2020). On the other hand, there is a position that findings from social science are not yet robust, reliable, or generalizable enough to make specific recommendations to society (IJzerman et al., 2020). What is your current impression of the situation, especially given that the issue directly related to your research theme has emerged?

Reply
In a classic paper, Meehl (1978) wrote, “I consider it unnecessary to persuade you that most so-called “theories” in the soft areas of psychology (clinical, counseling, social, personality, community, and school psychology) are scientifically unimpressive and technologically worthless.” This assessment may have been too harsh, and, even if appropriate at the time, it might not apply to psychological research 40 years later. Even so, Meehl described many issues that continue to challenge us, including those related to understanding the constructs we’re measuring (or: measuring what we actually want to measure), making valid causal inferences, and developing cumulative and integrative theories. The replication crisis and, relatedly, publication bias (and resulting effects on meta-analyses) should make us quite modest in our confidence in the applicability of research findings to public policy. Hence, I agree more with the more skeptical perspective of IJzerman et al. (2020) than the more optimistic perspective of Van Bavel et al. (2020). Even so, I think that recent methodological improvements show us the best way forward to making our science ready for policy recommendations. Publishing registered reports, where peer review is conducted before data are collected, will improve research practices and remove publication bias from the literature. Multi-lab collaborations will increase sample size and the reliability and generalizability of findings. And, related to your question, I hope that the current pandemic will redirect research interests toward questions with greater policy implications. I know that it has shifted my research goals. Until now, I have been interested in understanding aspects of the mind that have evolved to neutralize pathogens. Now, I would like to better understand how to encourage behaviors that limit the spread of respiratory pathogens – things like handwashing, self-isolation while sick, and creating barriers to aerosol transmission (e.g., facemasks).

お二人からの回答は以上となります。Tyburさんの回答に、2011年3月の自分を思い出しました。同じような感想を抱いた方は少なくないかと思います。現実社会にアプローチしたい気持ちと、手元の知識の確からしさや応用可能性を見定める慎重さと、そのバランスは人それぞれでしょうし、時代や状況によっても変わってくると思います。しかし常にそのバランスに注意を払っていることは、必要なのではないかと思います。お二人の回答が、皆さんがこの問題を考えていく上での手がかりとなれば幸いです。