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In our society, mutual helping is prevalent. Although we tend to take it for granted, the existence of mutually helping behaviors in large non-kin groups is unique to humans. Why is it that only humans engage in this kind of helping? Usually, we think that this behavior is due to some feeling, sentiment, or affection we have that make us want to help others. However, this then leaves the question of why is it that humans have such a psychology?


To this question, traditional psychology has been unable to provide a satisfactory answer. In our lab, our answer to this problem is that having such a psychology is adaptive to each person. In other words, the key concept for our research is that, in human society, there are some mechanisms that make a helpful psychology adaptive. We also contend that such a mechanism is not purely a matter of inheritance. Rather, people create such mechanisms themselves, whether or not they intend to do so. Studying the mutual construction of mind and society from this perspective is the core of micro-macro social psychology.

In addition to the example of the origin of altruistic behavior, there are many other topics that micro-macro social psychology can and should address, such as discrimination, changes in human relationships due to globalization, solutions to cooperation dilemmas and group living, such as, environmental problems, and methods for restoring fairness. Examining such issues will help us to understand society better. Why have human societies developed from the small-scale hunter-gatherer societies found when Homo-sapiens first appeared, to the large industrialized societies and highly advanced information technologies of modern society? Moreover, how will human societies change and develop in the future? Answering such big questions has been the dream of social scientists since the emergence of the field a century ago. And while this dream still remains unfulfilled since the late 20th century rapid development has been taking place. In our lab, regardless of how small our contribution may be, we aim to aid the development of social science research by utilizing a selection of fundamental approaches.

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Fundamental Approach

(1) Micro-macro social psychology

There are many phenomena emerging in our society. Why do they emerge? 

We tend to think that it is because people intend to make them happen or wish for them to occur. For example, the media often report that juvenile crimes are increasing in their number and seriousness and argue that the reason for this is that the quality of education by parents, communities, and schools has been decreasing over time. Therefore, they propose that the solution is to educate children to have more sympathy and a clearer sense of morality. In other words, such an argument proposes that what is happening in a society is caused by what is in the minds of the members of society. Let us consider some other examples. Although sex discrimination is prohibited by law, we often hear, at least in Japan, that a male candidate is more likely to be hired than a female candidate when the two display the same level of ability. Could this be because the company or the person in charge of hiring has a prejudice that females are inferior to males? In the modern world many environmental problems, such as global warming, are becoming ever more serious. In order to solve these problems, many people believe that it is necessary to change each individual’s mind so that they show more care and consideration about environmental problems. But is this really the case? The next example involves people refraining from activities as following the events of the Tohoku Earthquake in 2011 commercials were not broadcast and people refrained from having farewell and welcome parties, or simply having fun. But did these phenomena really occur because people intentionally decided to refrain from these activities? The final example to be considered is an economic recession. Nobody would desire an economic recession to happen and if the direct cause can be found in people’s minds, then the solution would seem to involve changing people’s minds so that they wish for an economic boom. But if this could be achieved, would this really cause the economic situation to change?
The above examples are all based around the idea that individual minds or behaviors cause social phenomenon directly. The logical structure is the same across all examples. However, the further you go with such logic, the more doubt you will have about the causal relationship. When we get to the level of economic trends it seems obvious that this event is not created directly by individual minds. If this was the case, then policy makers would not have any difficulty in creating economic booms. However, it is also true that these phenomena are not completely independent from people’s mind as, for example, levels of optimism amongst bankers can affect important economic decisions. How then should we understand the relationship between an individual’s mind and wider social phenomena?

The main message of micro-macro social psychology is as follows: while social phenomena at the macro-level ultimately consist of people’s minds and behaviors at the micro level, there is however, no direct causal relationship between them. Each individual thinks and makes their decisions and the aggregate of behaviors is visible and has an effect on a society. But this effect is not a simple aggregation of individual thoughts and behaviors as each individual does not make their decisions entirely independently from other people. An individual’s decision inevitably depends on the decisions of other, as for each individual there are a number of agents who influence their decisions, yet at the same time such agents and other people are also the targets of influence from the individuals choices. When such a mutually affecting process exists, social phenomena that people did not intend or expect can emerge. Unraveling this mutual construction of an individual’s mind and society is the main aim of micro-macro social psychology. The perspective this approach offers is similar to economic science but also incorporates a consideration of the relevant psychological processes in the micro-macro relationship. Such a consideration of psychological processes is thus the distinctive characteristic of micro-macro social psychology.

Adopting such a perspective, the answers to some of the questions presented above would be as follows:

  • Sex discrimination exists because people are embedded in an environment in which they have to engage in discrimination, and the environment itself is maintained by the very behavior of discrimination.
  • Self-restraint occurred because people were afraid of being denigrated for not doing so, thus the restraint could emerge even if each individual personally did not feel any desire to exercise self-restraint. Since many people displayed self-restraint, this in turn, made more people exercise self-restraint and the effect became visible at a societal level.

This type of understanding of social phenomena can have significant implications for social policies. For example, trying to change individual’s minds in order to resolve discrimination might be the wrong solution, a more productive approach might be to make people believe that non-discrimination was normative in society. For instance, one simple way to make this happen would be to enact a law that forced companies to hire equal numbers of males and females. Combining game theory, which offers a method to analyze the structure of the situation (i.e. the consequences of each possible combination of one’s own behavior and the behaviors of others) and an adaptationist approach, which acts as a framework through which various societal differences can be explained. micro-macro social psychology offers a unique approach which is now producing a lot of new research.

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(2) Game theory


Game theory is perhaps the most widely used method to analyze interactions among individuals. When there are multiple players, each of whom has multiple behavioral alternatives, game theory can be used to describe and analyze the various consequences of the different combinations arising from players’ choices.

When there are two players, game theory focuses on what happens within the dyad and when there are more than two players the focus shifts to what happens within the group.
Since the establishment of game theory, researchers have been analyzing the relationship between assumed behavioral principles and their consequences for a society. Game theory as an approach originated from the work of a mathematician and an economist in the middle of the 20th century, but it has developed dramatically from the later 20th century onwards. Recently, by using game theory as a common language, there has been an increasing integration of the disparate social sciences, which have traditionally been fractionalized. As a consequence an increasing amount of interdisciplinary studies that generate mutual influences between fields have begun to appear.

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(3) The Adaptationist approach


Humans are equipped with various psychological mechanisms but why do we have such mechanisms? The ultimate answer must be that “such mechanisms help (or have helped) us to adapt to the environment we are embedded in.”

The first discipline that introduced this idea explicitly was evolutionary psychology. According to evolutionary psychology, humans have been equipped with various psychological mechanisms because having such mechanisms has been adaptive during our evolutionary history. With our biology, various physical characteristics are recognized to exist because they have been useful during the evolutionary process and evolutionary psychology thus aims to expand this idea to psychological mechanisms. It is important to note, however, that what evolutionary psychology considers as our primary adaptive environment is usually that experienced by small-scale hunter-gatherer societies during the Pleistocene. Thus, what had been adaptive in such environments is not necessarily adaptive in the modern world. For example, humans crave tastes of salt and fat.
This was adaptive when individuals faced uncertainty and a paucity of food resources as was the case during the Pleistocene, but such drives may now actually prove maladaptive in a modern society, such as Japan, because overconsumption of such foods can trigger various lifestyle-related illnesses.
However, the adaptationist approach itself is a much wider concept. Although evolutionary psychology usually focuses on biological evolution characterized by genetic changes, the adaptationist approach does not limit itself solely to consider biological processes. Around 10,000 years ago, the Pleistocene ended, and since then human societies have branched into various types. In each society moreover, there can be adaptive psychological mechanisms, which are unique to that context. For example, although Japan and the U.S. are both modern societies, the specific adaptive psychological mechanisms are likely to be quite different. This idea is consistent with the psychological and anthropological research on culture. However, despite the shared topic, why there are cultural and societal differences tends not to be addressed in these disciplines. The adaptationist approach alternatively proposes that such differences exist because people acquire psychological mechanisms that are adaptive in each specific environment. This does not necessarily mean, however, that the psychological mechanisms have a genetic basis. Rather, the adaptationist approach considers that people living in each society acquire adaptive psychological mechanisms during the socialization process. As such, the various psychological mechanisms include some that people would have no intention of acquiring, some that they do not even realize they have acquired, as well as mechanisms that they consciously intend to acquire so that they can be successful in their society. Consequently, the adaptationist approach is a broader approach, which includes cases in which psychological mechanisms are acquired without any attendant genetic change and without conscious reflection. In short, the target of adaptation is not only the physical and external environments, which have been the focus of evolutionary psychology but also the social environment, which consists of the behaviors of others. Of course, it is also true that others’ behaviors are a source of influence on one’s own behavior in addition to being a target of behavior. In this sense, the adaptationist approach and the approaches outlined in (1) and (2) above are mutually complementary.

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Fundamental Approach

Department of Behavioral Science,
Graduate School of Letters,
Hokkaido University

Nobuyuki Takahashi’s lab

Kita-10, Nishi-7, Kita-ku
Sapporo, Hokkaido 060-0810

Phone: +81-11-706-4153 Fax: +81-11-706-3056