Why are people so strongly motivated to have relationships? According to a landmark paper by psychologists Roy Baumeister and Mark Leary it’s because of a fundamental “need to belong.”1 The “belongingness hypothesis” states that people have a basic psychological need to feel closely connected to others, and that caring, affectionate bonds from close relationships are a major part of human behavior.
Here is an overview of the evidence for this hypothesis, point by point:
- Forming social bonds – People readily form relationships with others without being paid or forced to do so, and do so even under adverse circumstances. For example, infants and children will form attachments to others even though they have little or no knowledge of their social world and are incapable of calculating benefits or costs to these relationships.
- Not breaking bonds – People are eager to have close relationships and are reluctant to break them once formed, even when the relationship is marked by distress, conflict, or even abuse. People often avoid permanent separation (breakups, divorce, death), even when the costs of staying in the relationship are greater than leaving.
- Cognition – When we feel close to others, our thoughts change such that a cognitive “merging” effect occurs; people begin to include aspects of their relationship partner in their own self-concept. The boundaries between individual partners break down in relationships, and people think of their own fate as being intertwined with the fate of others.
- Emotional highs and lows – No matter how you slice it, relationships carry immense emotional weight. People feel a great deal of positive emotion (e.g., joy, bliss, love), especially during the early stages of relationships. People also feel lots of negative emotions and distress (e.g., anxiety, anger, jealousy) when things aren’t going well.
- Consequences of deprivation – When people lack meaningful close relationships with others, they suffer. Specifically, married individuals are healthier, less stressed out, and are expected to live longer than single individuals (not to stigmatize singles here). Close relationships boost people’s immune systems.
- Partial deprivation – Even within highly satisfying relationships, being separated from a loved one (or having restricted interactions) produces distress and sadness. When couples are separated (through things like work-related distance, military duty, or even prison) they report more loneliness.
- Satiation and substitution – There is such a thing as too many close relationships. People strongly prefer to have (and are only capable of having) a few very close friendships and a larger number of casual friendships. In this case, quality is more important than quantity. Relationships take time, effort, energy, and resources, so it makes sense that any individual person would experience a “satiation point” after their belongingness needs are fulfilled. In addition, when a bond is broken, people will readily pursue another in its place. This is not to say that one person is as good as the next, but people are resilient and in the aftermath of a painful loss or separation, new relationships are formed.
- Innateness, universality, and evolutionary perspectives – People throughout the world are born with the ability and motivation to form close relationships, and this universal tendency is adaptive. Children who form close emotional attachments to their parents are less likely to wander off, get picked off by a predator, or fall victim to some other natural danger. Thus, relationships protect us from harm when we are young and vulnerable.
Of course, some people need closeness, intimacy, attachment, and love with other people more than others. But this much is clear: in general, people need close, caring, intimate relationships marked by emotional depth. In words of the Baumeister and Leary, “it seems fair to conclude that human beings are fundamentally and pervasively motivated by a need to belong, that is, by a strong desire to form and maintain enduring interpersonal attachments.” I think it’s also fair to conclude that without the need to belong, the science of relationships would not exist.
1Baumeister, R. F., & Leary, M. R. (1995). The need to belong: Desire for interpersonal attachments as a fundamental human motivation. Psychological Bulletin, 117(3), 497-529.
Dr. Dylan Selterman - Science of Relationships articles | Website/CV
Dr. Selterman's research focuses on secure vs. insecure personality in relationships. He studies how people dream about their partners (and alternatives), and how dreams influence behavior. In addition, Dr. Selterman studies secure base support in couples, jealousy, morality, and autobiographical memory.