More than one scheme
The title suggests a single medieval doctrine of three ages, but medieval writers actually used several ways of dividing a lifespan. The simplest was indeed a division into three: youth, maturity and old age. Others used four stages (often matched to the seasons), six, seven or even more. The number depended on the purpose. A doctor, a preacher, a poet and a lawyer could each pick the scheme that suited their needs, and none of them was official.
So the three ages are best seen as the basic frame, with other schemes adding detail. All of them shared a belief that human life has a natural shape and that each stage has its own qualities and duties.
The basic three
Youth was the period of growth and learning. It was seen as a time of energy, appetite and impulsiveness, when a person was formed by training and discipline. For boys of the nobility this might mean being sent to another household to learn manners and arms, a path that began with knightly training. For a craftsman’s child it might mean apprenticeship, often governed by written apprenticeship contracts. Girls learned household skills, and in some cases reading and religious devotion. Medieval childhood itself was short by modern standards.
Adulthood, sometimes called maturity or the prime of life, was the period of responsibility. It was when people were expected to work, marry, hold land or run a business, raise children, bear arms or hold office. Writers regarded it as the time when judgment and strength were at their best. Many of society’s obligations, such as service to a lord, were carried out in this stage.
Old age was the stage of decline, but also of reflection. It was associated with experience and wisdom as well as physical weakness. Moralists encouraged the old to prepare for death through prayer and charity. Some people retired to a monastery in later life, and others handed their property to heirs in exchange for support. Respect for the old was an ideal, though the realities for poor elderly people were often harsh. The end of life brought its own funeral customs.
Longer schemes
The most influential longer scheme came from early authors, including Isidore of Seville, who wrote in the early seventh century and passed on a division into six ages: infancy, childhood, adolescence, youth, maturity and old age. Isidore and later writers attached approximate years to them, such as infancy lasting to about seven and childhood to about fourteen, with later stages ending around twenty-eight, fifty and beyond. The numbers varied between authors and should be taken as rough guides rather than fixed rules.
The six-part pattern also echoed a religious idea: the “six ages of the world” from creation to the Last Judgment, which writers like Augustine had used in their view of history. Comparing the stages of a person’s life to the stages of the world’s history was a way of giving personal life a place in the divine plan.
Other writers favored four stages, matching the four seasons and the four humors, an idea tied to the natural cycle. Another popular scheme, found in later medieval art and literature, had seven ages, sometimes tied to the seven planets of the older cosmos. The famous seven ages speech in Shakespeare’s As You Like It comes from this long tradition, though it was written after the Middle Ages.
Ages in art and literature
Artists sometimes illustrated the ages as a series of figures: a child with a toy or hobby horse, a young person hawking or courting, a mature man in fine clothes, and an old man with a stick. In some images the ages are arranged as a rising and falling staircase, with the peak in the middle. This arrangement gave a clear picture of growth and decline, and it often carried a moral message about the shortness of life and the need to be ready for death. Scenes like these often appear in illuminated manuscripts and in printed books at the end of the period.
Schemes versus real life
It would be a mistake to think that medieval people moved neatly through fixed stages. Legal and religious rules did set certain ages: canon law, for example, allowed marriage from about twelve for girls and fourteen for boys, though many couples married later, and practice varied by region and class. Entering a trade, taking vows or holding land each involved their own thresholds. None of these corresponded exactly to the ages of the scholars.
Life expectancy at birth was low in the period, mostly because many children died young. People who survived childhood often lived into their fifties, sixties and beyond. Because of this, the notion that people were “old” at forty is a misunderstanding. The theoretical schemes shifted the beginning of old age to a point later than that.
Why the ages mattered
The ages of man gave medieval people a way to talk about what was appropriate at each point in life. A young man was forgiven some folly but expected to learn, and an old man was expected to be sober and give counsel. The schemes also served as a reminder that life is a journey with a fixed end, an idea that ties in with preaching on the deadly sins and on preparation for death. For modern readers they are a useful reminder that the stages we take for granted, such as adolescence or retirement, are partly cultural categories.