Men lean toward things, women toward people. Does it matter?

Any discussion of traditional relationship roles eventually reaches an uncomfortable modern question: are men and women actually different in ways that could have influenced the division of labour? The answer is yes. The harder question is what those differences mean.

Men and women overlap enormously. There are physically strong women and physically weak men. There are mechanically obsessed women and deeply nurturing men. There are female engineers and male nurses. Individual people should be treated as individuals.

But populations can still differ on average. And when societies are formed by millions of individuals interacting over generations, averages can influence institutions.

Things and people

One of the largest and most consistently observed psychological sex differences concerns vocational interests. It is often summarized simply: Men tend to be more interested in things. Women tend to be more interested in people. That is not merely a stereotype.

A major 2009 meta-analysis by psychologists Rong Su, James Rounds, and Patrick Armstrong combined data from 503,188 people. The researchers found a large average sex difference on the Things–People dimension, with men more things-oriented and women more people-oriented. The reported effect size was d = 0.93, unusually large by the standards of psychological sex-difference research.

Men also showed stronger average interests in what psychologists call Realistic occupations—work involving machinery, tools, physical objects, and practical systems. Women showed stronger average Social interests—work involving teaching, helping, caring, and interacting with people.

A later study found that these patterns helped explain why male and female representation differs across STEM fields. Engineering is highly things-oriented and remains disproportionately male, while social sciences and medical services are considerably more people-oriented and attract more women.

This does not mean culture plays no role. It certainly does. But the pattern is large, replicable, and not well described as an invented stereotype with no measurable basis.

Physical differences also mattered

Modern office work minimizes many physical differences between men and women. A spreadsheet does not care how much you can lift. Agrarian economies did. So did mining, logging, seafaring, construction, hauling, hunting, military service, blacksmithing, and much early manufacturing.

Men are larger and stronger on average, with the difference particularly pronounced in upper-body strength, although the precise size varies by task and population. Today that may matter relatively little to an accountant. Several centuries ago it could materially affect productivity and safety.

Technology progressively reduced this advantage. A tractor substitutes mechanical power for muscle. A forklift substitutes hydraulic power. Power tools substitute motors. Cars and trucks substitute engines for walking and hauling. The importance of strength to earning capacity consequently declined across large portions of the economy.

Reproduction creates an asymmetry

There is one biological difference no social system can eliminate: women become pregnant, women give birth, and women breastfeed. Men do not.

Modern technology can reduce the practical consequences. Contraception allows family size and timing to be controlled. Formula and breast pumps increase flexibility. Obstetric medicine reduces reproductive risk. Daycare allows parents to purchase childcare. Parental leave allows temporary withdrawal from work. Historical families did not have most of these options.

In high-fertility societies, motherhood could consume enormous amounts of time and energy. Women historically had many children because both fertility and child mortality were high. In 1800, five to seven births per woman were common, while child deaths remained tragically frequent. That made labour specialization around reproduction extremely difficult to avoid.

Biology is not destiny

None of this proves that a man should become an engineer or a woman should stay home. Average differences do not dictate individual lives. A population distribution is not a command.

Suppose men average taller than women. That tells us something meaningful about populations. It does not tell us whether a particular woman is taller than a particular man. Interests work similarly. Many women are more things-oriented than most men. Many men are more people-oriented than most women.

The evidence supports something more nuanced: Men and women are broadly similar human beings with overlapping distributions, but some average differences are substantial enough to influence behaviour, occupation, and social organization.

From differences to social roles

Historical roles probably emerged from several forces operating together. Physical capacity mattered. Pregnancy and childcare mattered. Economic necessity mattered. Technology mattered. Custom mattered. Law mattered. Religion mattered. Average preferences probably mattered too.

A society in which men were more likely to enjoy tools, machines, hunting, construction, and object-oriented work—and were physically better suited to some demanding forms of it—would probably develop somewhat different patterns from a society in which no such differences existed. Likewise, stronger average female orientation toward people and care may have reinforced work involving children, health, social coordination, and household relationships.

Culture then formalized those patterns. A practical tendency could become a custom. A custom could become an expectation. An expectation could become a law or religious teaching. Eventually, the pattern might continue even after some of the original reasons weakened.

Modernity changes the constraint, not necessarily the preference

Modern economies have radically changed what men and women must do. They have not necessarily made male and female averages disappear. The things–people difference remains visible even in modern populations with extensive educational and occupational freedom.

That leads to an interesting possibility. As external restrictions weaken, some differences may decline because they were socially imposed. Others may persist because people genuinely prefer different things on average. The challenge is determining which is which.

We should therefore be cautious about treating every statistical difference between men and women as evidence of oppression. We should be equally cautious about treating every statistical difference as proof of biological destiny.

Human behaviour emerges from biology interacting with culture, opportunity, incentives, technology, and individual personality. Traditional relationship structures were likely produced by the same interaction.

The important point for this series is straightforward: Traditional male and female roles did not arise in a world where men and women were physically, reproductively, and psychologically interchangeable. They arose in a world where those differences mattered economically.

Modernity has reduced many of the consequences. It has not erased the underlying question.

Research & references

• Rong Su, James Rounds, and Patrick Armstrong, “Men and Things, Women and People: A Meta-Analysis of Sex Differences in Interests,” Psychological Bulletin (2009).
• Rong Su and James Rounds, “All STEM Fields Are Not Created Equal,” Frontiers in Psychology (2015).
• Kritzer et al., “Sex Differences in Strength at the Shoulder: A Systematic Review” (2024).
• Hoff et al., “Normative Changes in Interests from Adolescence to Adulthood,” Psychological Bulletin (2018).
• Our World in Data, historical fertility and child-mortality datasets.