Marriage is a long-standing social and legal institution, and studying it through social sciences can change how we view it. Recognizing the cultural and psychological aspects of marriage and the shifts these aspects are currently experiencing is also important. For instance, separating marriage from childbirth and the rearing of children was a significant part of recognizing same-sex marriage. Similarly, understanding the different types of relationships people might form, as well as the shifting roles each partner plays in a marriage might inform future changes to the institution. Furthermore, understanding the psychology of marriage can help individuals form stronger marriages. You point to the changes in marriage over the years and the relation between western (European) views on marriage and American views. This is particularly pertinent as marriage is such an important part of many cultures. As more cultures are recognized and acknowledged as part of the global society, studying and understanding how to reconcile their differences and potentially conflicting values becomes critical to maintain it.