In my current book project, I explore the question of why we know how old we are. In the 21st century, our chronological age is deeply embedded in society—through legal age limits or birthday celebrations, for example. Yet, with aging populations and growing individualization in the Western world, we are increasingly questioning the downsides of chronological age. Don’t fixed age limits treat everyone the same, even when individual traits might matter more? And doesn’t chronological age often feel stigmatizing and restrictive, especially for older people—think of the phrase, "Age is just a number"?
My research traces how, between the 18th and 19th centuries, European states began using chronological age as a category of power—for example, to conscript soldiers. At the same time, elites came to believe that anyone who did not know their age was uncivilized. This combination of state pressure and cultural emulation of elite manners created two powerful forces that gradually made European societies more and more “age-conscious". Thus, the project's title: The dawn of "the Age of Age" in which we still live, despite some misgivings.
See those little scribbles of numbers on the bottom of the source (a baptism certificate)? A village priest calculated the ages of the deceased - probably to note them in the parish records and funeral sermons. Interest in age grew from all sides of 18th-century society. As parish registers recorded baptisms, they could serve as proof of age.