What does Gillis claim about cohabitation in the past?

Gillis argues that cohabitation in the past existed as a common law practice, meaning that couples could live together and form relationships without the formal institution of marriage. This reflects historical legal systems where cohabiting arrangements were sometimes acknowledged, allowing partners to enjoy certain rights and responsibilities similar to those of married couples, albeit without formal legal recognition.

Understanding this context helps illustrate how societal perceptions of cohabitation have evolved over time. While there may have been social stigmas attached to cohabitation, it was still a recognized practice within certain legal frameworks, indicating that many couples chose to live together outside of traditional marriage. This perspective is crucial for understanding the shifts in family structures and union types over the years.