Study on the Population and Life Course Dynamics in the First and Second Demographic Transition and Their Future Prospects

我们研究了被称为人口转变(DT)的人口动态过程，既有经典的，也有所谓的第二次，以及它与社会和经济转型的关系。我们将日本的人口下降和老龄化定义为一个名为“后人口过渡阶段”的历史制度，然后系统地考察了该制度下社会、经济和政治发展与人口变化之间的相互关系。人口增长伴随老龄化的结束被视为DT之后的一个不可避免的过程。日本是这一进程中的领头羊，变化迅速，有些过度。我们不仅关注人口层面的宏观现象，还关注生命过程中个体层面的变化，如长寿、婚姻和生育的转变，以及国际移民的增加。在日本人口结构转型的过程中，我们发现了许多鲜明的特征。

We studied population dynamisms processes known as the demographic transition (DT), both classic and so called second one, as well as its relationships with social and economic transformations. We defined population decline and aging in Japan as a historical regime named "post demographic transition phase," then systematically examined interrelationships between social, economic, and political developments and population changes in that regime. The end of population growth accompanied by aging is seen as an inevitable process following the DT. Japan is the leading country in this process with rapid and somewhat excessive changes. We focused on not only the macro phenomena at population level but also individual level changes in the life course such as longevity enhancement, transformation of marriage and childbearing, and increasing international migration. We found many distinctive features in the process of Japanese demographic transitions.