Ariès’s book is certainly a controversial one, and you are correct to suggest that its central thesis – which we might sum up as the argument that the modern idea of childhood was invented in the seventeenth century, and that, until this point, children were considered to be small adults, and were marginal to society – is not terribly well-regarded nowadays. However, it's not really accurate to suggest that Ariès has nothing at all to tell us about the history of childhood or that there's nothing left to learn from a reading of his book. It's certainly also possible to argue that we can draw important things from thinking about Ariès and his arguments.

I published an analysis of Centuries of Childhood for Routledge a few years ago – it was written by Eva-Marie Prag, a Columbia historian, and Joseph Tendler, a specialist in the historiography of the Annales school. They offer a nuanced view of the ongoing debate over the book:

Scholars have continued to work to determine when the concept of childhood emerged. A 2007 collection of essays on childhood in the Middle Ages shows widespread agreement that although parents felt love and concern for their children, the Middle Ages did not feature the sentimental glorification of childhood that is evident in many countries today. Yet these same accounts strongly disagree with Ariès that children had no special status at all. This implies that while childhood in the Middle Ages may have been very different from today, other manifestations of childhood may very well have existed. Scholars have also investigated whether Ariès used the correct term by referring to the “invention” of childhood. The British historian Hugh Cunningham notes that while Ariès does talk about “invention,” he was actually referring to our contemporary idea ofchildhood, and not implying that parents in the past did not care for their children. This confusion was not helped by Ariès’s use of the word “discovery” to describe the emergence of modern childhood.

Ariès’s central claim that the notion of childhood is a recent invention continues to be controversial. The general public and scholars alike have difficulty accepting that childhood is an idea constructed from class, gender, religion, and race, among other factors. The British historian Linda Pollock still seeks to prove that the relationship between child and parent is universal and constant in nature. Pollock’s argument is consistent with the views of the American medieval historian Barbara Hanawalt, who insists that Ariès’s sources were not strong enough to prove his point.

The British historian Nicholas Orme speaks for many medieval historians when he attempts to disprove that our idea of childhood was invented in the way Ariès describes. However, as Hugh Cunningham notes in his evaluation of the field of childhood studies, many of the criticisms made of Centuries of Childhood can be attributed to the widespread but faulty assumption that Ariès’s stance “was a slur on the Middle Ages.” Ariès did not mean that medieval children were not loved, but rather that they were not pampered—for example, they were expected to work at an early age.