My favorite monument looks like a married couple. It was draped in marble flowers and guarded by the fat angels, with two stone portraits, with a knotted cloth and a script describing an intimate bond: "The beautiful and uninterrupted marriage of the soul, unseparated companionship in thirty-six full years". But this memorial has nothing to do with the husband and wife. It commemorates a kind of friendship - two men, Sir John Finch and Sir Thomas Baines, Renaissance doctors who traveled, worked and lived together in the 1600s and were buried side by side at Christian College in Cambridge. "They blend their interests, destiny, counseling, and negation in their lives," their tombstone reads: "may be in the same way, death, and finally mixing their divine ashes."

This vigorous expression of love is far from the popular description of today's male friendship, which tends to portray men as fragile suffering, or to form bonds unless women prompt in their lives. Of course, Finch and Baines might be a couple. They live in a culture that criminalizes homosexuality, where "friendship" may be a cover. But the Platonic relationships will not be unique.

Many historians have a ritual to get rid of the 21st century complacency. When my friend Joe sat on her desk writing about the 19th century America, she tried to remember that Pigs had been wandering the streets of New York at that time. Going to the monument of Finch and Baines was my trick when writing my latest book, History of Friendship. In an era when female friendship is widely idealized - Sex and the cityReading four and pink glitter t-shirt The best friend forever- Finch and Baines' memorials helped me remind me that the worship of female friendship is not always the norm, and the way friendship is now viewed may not be the way to be seen forever.

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I am an emotional historian: I study how cultural narratives work on people’s behavior as individuals and how socially changing factors play a role in our hearts and families. Scholars in my field often talk about the concept of “emotional community” to understand how behaviors associated with specific feelings change in time and place. An emotional community shares expectations of what emotions should be felt, i.e. what is shown, hidden, and how each emotion should be expressed. Such rules are enforced through institutions such as schools and courts, as well as literary, artistic and family life rituals.

As the emotional rules of society change, the feelings people expect, including friendship, will also change. Psychologists show that friendships are far from following a common template, but rather that “styles” vary slightly from place to place. According to psychologist Roger Baumgarte, certain cultures, such as American culture, seem to favor a more “independent” style of friendship in which friends respect each other’s autonomy very much and may feel uncomfortable if they feel someone crosses the border. In other cultures, such as Cuba or Chinese, people are expected to “intervent” more in the lives of friends and may feel neglected if it doesn’t help. While this kind of research can quickly give way to reducing stereotypes, it does shed light on diverse expectations of friendship.

These expectations will also change over time. For example, Finch and Baines’s 17th-century emotional communities were shaped by highly romantic ideas about male friendship. These two people lived in a period of amazing knowledge transformation in Europe, when artists, politicians, scientists and philosophers rediscovered great works of classical antiquity through scholars from the Golden Age of Islam and hoped to make their ideals their own.

A such work, Aristotle's Nicomanman moralityWritten in the fourth century BC, friendship is divided into three levels. The two levels at the bottom are ordinary friends, which he calls friendly and pleasant friendships (women are said to be the only ones capable of). Aristotle wrote that friendships in utilities are based on “business awareness” of mutual assistance and efforts. Pleasant friendships are bonds formed through transfer and entertainment: you may be inclined to friends because they will make you laugh, or you may join them in games because they support your favorite athletes. But Aristotle called the third layer of friendship "perfect" is another matter, the bond between two people "similar virtues" who see each other as "second egos." As later philosophers explained, as later, it was as if "a soul resides in two bodies." That's what Baines and Finch think. They strive to be "perfect" friends and by all points they seem to succeed.

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French philosopher Michel de Montaigne is another Renaissance figure who considers himself a "perfect" friend, and his essay "About Friendship" continues to influence writing today. In connection with lawyer and writer Etienne de la Boétie, de Montaigne, he believed that he had found an ideal friendship that only a generation could only hope to achieve, and his papers were a soaring spike in their extraordinary connection. In one of the most cited lines in friendship history, he wrote: "If you press me to say why I love him, I don't think it can be expressed, except for the answer: 'Because it's him: because it's me.'"

Like other intellectuals at the time, de Montaigne did not think women could have such ideals. He wrote that the female brain could not stand this "knotted cloak, so long, so closely drawn". His claim is based on the misogynistic medical theory of the era, which argues that women's brains are colder and weaker than men. Women are willows, explained Margaret Cavendish, a scientist and poet of 1655, that it is possible to bend in the smallest draft, rather than a solid oak. In this way, most women are declared too swing, capricious and stupid for the promises required for true friendship. People also think their romantic relationship with men distracts them. François dela Rochefoucauld, a French nobleman in the 17th century, wrote: "The reason most women are so little affected by friendship.

Women’s friendships that began in this era are not usually commemorated on stones or glorified in the prosperity of poetry. In the archives, their stories look like fragments compared to the large, easily accessible corpus of male friendships. But of course they exist. In my research, I found evidence of women’s bonds in waste and debris – women grieve at the deceased’s friends or help each other through illness, proving that friends form families and raise children, jointly run common businesses, defend others in court. People know the power of these alliances. Friendship provides a world for female agents that are not designed for them. Maybe no wonder their friendship is often dismissed.

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Within 100 years of burial of Finch and Baines, their emotional community rules began to change. The second part of the 18th century was the revolutionary fever and social reform period throughout Europe and the United States. As abolitionists, women’s rights and momentum in anti-poverty movements have also inspired motivation, as are discussions about emotions and sympathy (old words Empathy). In this new era of sensitivity, poets, artists and philosophers began to speak about the sensitivity of "female thoughts" in a pious tone. They helped promote the idea that women have special skills in friendships and are able to have a deep emotional connection with the poor, the disenfranchised, and one another.

But by the 19th century, this belief in women’s empathy had become a new ideal of middle-class Victorian femininity: “Ange of the House.” That perfect woman should have been gentle, loving and eternal support. Pious friendship is seen as a testament to her compassionate nature. Girls’ Generation bonds are considered as the practice of affection and sacrifice necessary for future roles of wife and mother. Often, girls are filled with stories of highly romantic female friendships: a popular nursery series depicts two friends, Beatrice and Alice, who “love each other deeply” and “whose arms between each other will sit in the deep shadows of trees and listen to the notes of the cuckoo.” In Victorian novels, girls who enjoy intimate childhood bonds – think of Jane Eyre and Helen Burns Villetif anything, unfortunately got married.

During this time, the romantic friendship between men did not completely lose. Photos from the 1850s to the early 1900s showed male friends holding hands or hanging from each other; during this period, emotional letters abounded between men. But by the second half of the 19th century, new narratives about men’s friendship were on the rise. Some people begin to describe male friendship as mean and superficial. As homosexual culture becomes more and more obvious, European sexologists are shocked by fear of “sexual inversion,” a growing sense of self-awareness of male intimacy. In 1863, British feminist campaigner Frances Power Cobbe read widely Fraser Magazinehere, she reiterated that at that time, it was a familiar story about male and female friendship. Cobb wrote that women's friends enjoy "the purest pleasure and the most selfless person", and for men, friendship is nothing more than forming an "acquaintance" in the club.

In some ways, Americans still live among the ghosts of these Victorian predecessors, keeping women at a high level of intimacy and portraying male bonds as clumsy and incompetent. We also live in an era of social dispersion where experts worry about loneliness and isolation and are confused about how people are brought together. To promote more connections, we need to revisit our emotional rules – rules worth keeping, and without which ones, we might be better. As historians, I can tell you: If we want to reimagine the terms of friendship, we can.

*LEAD image credit source: fitzwilliam Museum/Bridgeman Images; Harris Brisbane Dick Foundation/Metropolitan Royal College of British Architects/Metropolitan