Men and Women Are More Similar Than We Pretend

People talk about men and women as if we're two completely different kinds of creatures.

Men think like this.

Women think like that.

Men are naturally suited for this.

Women are naturally suited for that.

Entire personalities are sometimes explained with one word:

gender.

But biologically, the reality is much less dramatic.

A man and a woman are both human beings built from almost exactly the same basic biological machinery.

We have brains.

Hearts.

Lungs.

Kidneys.

Livers.

Bones.

Muscles.

Nerves.

Blood vessels.

Eyes.

Ears.

Immune systems.

Digestive systems.

The same basic cellular machinery.

The same basic need for food, water, oxygen, sleep, relationships and stimulation.

The differences are real.

But they exist inside an overwhelmingly shared human architecture.

Start With the Body

Imagine designing two completely different robots.

You might give them different processors.

Different sensors.

Different operating systems.

Different communication protocols.

Different power supplies.

Different mechanical structures.

Now compare that with a typical man and woman.

Both have the same basic skeletal plan.

Two arms.

Two legs.

A vertebral column.

A skull.

A rib cage.

A pelvis.

Both use skeletal muscles to move those bones.

Both use motor neurons to activate those muscles.

Both use lungs to exchange oxygen and carbon dioxide.

Both use a heart to circulate blood.

Both digest carbohydrates, proteins and fats.

Both use glucose and fatty acids for energy.

Both generate ATP.

Both have immune systems.

Both have essentially the same major brain structures.

We're clearly variations of the same biological design, not two independent designs.

So Where Are the Differences?

Some of the most obvious differences involve reproduction.

Typical male and female reproductive anatomy differs.

There are differences in chromosomes in typical XX and XY development.

There are different reproductive organs.

And there are differences in average concentrations and patterns of sex hormones such as testosterone and estrogen.

These hormones influence development throughout life.

That produces some visible average differences between adult men and women.

But here's where conversations often become confused.

A biological difference doesn't automatically imply a completely different psychological creature.

Testosterone Produces Some Very Real Differences

Testosterone is important in male sexual development and contributes to characteristics including muscle and bone development. Adult males typically have substantially higher circulating testosterone concentrations than adult females. (ncbi.nlm.nih.gov)

This matters.

After puberty, men on average develop considerably more muscle mass and greater upper-body strength.

Average body composition differs.

Average hemoglobin levels differ.

Bone dimensions and some skeletal characteristics differ.

This is one reason elite male and female athletic performance differs substantially in sports where strength, speed, power and aerobic capacity are major determinants.

So saying:

"Men and women are exactly physically identical."

would obviously be wrong.

But saying:

"Men are physically stronger on average."

is very different from saying:

"Therefore men are better at everything."

Strength matters enormously when you're trying to deadlift 300 kilograms.

It matters much less when you're writing software.

Imagine Two Programmers

A man and a woman sit next to each other.

Both are given:

Design a scalable notification system capable of processing
10 million notifications per day.

What advantage does having greater average upper-body muscle mass provide?

Essentially none.

Neither person is going to bench-press Kafka.

The problem requires:

reasoning,

knowledge,

memory,

abstraction,

communication,

experience,

and creativity.

Most of the obvious sexually dimorphic physical characteristics simply aren't particularly relevant to the task.

That's an important distinction.

A biological difference matters only when it affects something relevant to the activity being performed.

Humans Have Enormous Individual Variation

Suppose the average man is stronger than the average woman.

That does not mean every man is stronger than every woman.

A trained female powerlifter can obviously be stronger than millions of men.

Population averages tell you something about populations.

They don't perfectly predict individuals.

This distinction gets lost constantly.

Imagine two overlapping distributions.

One distribution might have a higher average.

But there can still be enormous overlap between them.

Human characteristics often work this way.

Sex can help explain some population-level variation without becoming a deterministic description of every individual.

Height Is an Easy Example

Men are taller than women on average in most populations.

But imagine:

Arjun is 165 cm.

Ananya is 178 cm.

Saying:

"Men are taller than women."

doesn't magically make Arjun taller than Ananya.

The accurate statement is:

Men are taller on average.

Once you meet an individual person, measuring the actual person is usually more useful than guessing from the population average.

The same reasoning should be applied much more often.

The Brain Is Where Things Become More Complicated

Male and female brains aren't perfectly identical.

Researchers have found average sex-associated differences in some brain measurements and patterns.

But brain structure and human behavior are enormously complex.

There is substantial overlap between men and women, and researchers caution against treating brains as belonging to two completely distinct categories. Reviews of neuroscience research describe human brains as combinations or "mosaics" of characteristics rather than consistently male or consistently female across every feature. (pnas.org)

That makes intuitive sense.

There isn't one brain architecture for:

HUMAN MALE

and another completely different architecture for:

HUMAN FEMALE.

There are human brains influenced by genetics, hormones, development, environment, learning and individual experience.

Hormones Aren't Exclusive Either

We often talk as though:

men = testosterone

women = estrogen.

That's misleading.

Men and women both have androgens and estrogens.

The concentrations, sources and patterns differ.

Testosterone isn't some molecule exclusively installed in men.

Estrogen isn't exclusively installed in women.

Human endocrine systems share much of the same machinery while operating with important average differences.

Again:

same basic system, different parameters.

Culture Adds Another Layer

Now things become even harder to separate.

Suppose boys are encouraged from childhood to:

take risks,

play competitive sports,

hide fear,

build things,

and be assertive.

While girls are encouraged to:

be cautious,

be agreeable,

focus on appearance,

avoid physical confrontation,

and behave differently socially.

Twenty years later, researchers observe behavioral differences.

How much came from biology?

How much came from social expectations?

How much came from different experiences?

How much came from interactions between all three?

That's extremely difficult to untangle.

Humans don't grow inside controlled laboratory environments.

Biology affects behavior.

Culture affects behavior.

Behavior changes environments.

Environments can influence biological development.

Everything interacts.

This Is Why Stereotypes Are Such Bad Prediction Tools

Suppose someone tells me:

"Women aren't interested in computers."

Even if some survey somewhere found an average difference in interest, that tells me almost nothing useful about the woman standing in front of me.

I can simply ask her:

"Do you like computers?"

Now I have information about the actual individual.

Why use a weak statistical proxy when I can observe the thing I actually care about?

The same applies in the opposite direction.

"Men aren't emotional."

"Women are more caring."

"Men are logical."

"Women aren't competitive."

These statements take complicated distributions influenced by biology, culture and individual experience and collapse them into crude rules.

Humans are more complicated than that.

Where Sex Differences Matter, We Should Acknowledge Them

There is no reason to pretend biological sex is irrelevant.

Medicine is an obvious example.

Reproductive biology matters.

Pregnancy matters.

Hormone concentrations can matter.

Drug metabolism can sometimes differ.

Disease prevalence can differ.

Body composition matters.

Athletic competition can require sex-related considerations.

Ignoring genuine biological differences isn't equality.

It's just inaccurate biology.

But exaggerating those differences into two entirely different categories of human personality is equally inaccurate.

A Better Model

Instead of imagining:

MAN WOMAN
| |
completely completely
different different
system system

I think a better approximation is:

HUMAN
|
-------------------
| |
MALE FEMALE
| |
variations variations
\ /
enormous individual
variation

Most of the machinery exists above the split.

The heart didn't need to be reinvented.

Neither did the lungs.

Neither did neurons.

Neither did vision.

Neither did digestion.

Neither did memory.

Neither did the basic architecture required for intelligence.

Evolution modified parts of an existing human developmental system.

Think About What Actually Determines Success

Suppose I'm hiring a software engineer.

I care about:

Can you program?

Can you reason?

Can you learn?

Can you communicate?

Can you understand unfamiliar systems?

Can you debug?

Can you take responsibility?

Can you build things?

Knowing someone's sex gives me dramatically less useful information than simply evaluating those abilities directly.

The same applies to enormous parts of modern life.

A surgeon doesn't perform surgery with testosterone.

A CEO doesn't negotiate using biceps.

A scientist doesn't solve equations with bone density.

A programmer doesn't compile JavaScript using hemoglobin.

Many historical differences in what men and women did existed partly because physical strength, reproduction, pregnancy, childcare, property rights, education and social institutions mattered enormously.

Modern technology has reduced the importance of some physical constraints.

A forklift doesn't care how much you can deadlift.

A computer doesn't care how hard you can throw.

The internet doesn't care whether the person writing brilliant code is male or female.

Technology Makes Many Biological Differences Less Important

Imagine agriculture thousands of years ago.

Physical capacity could substantially influence how much work someone could perform manually.

Now give someone:

a tractor.

Suddenly human horsepower matters much less.

Give someone:

an excavator.

A crane.

A forklift.

A computer.

Industrial machinery.

Automation.

The more technology amplifies human ability, the less many raw physical differences determine what an individual can accomplish.

This is one of the most interesting effects of technology.

Machines don't merely increase human capability.

They can reduce the importance of biological inequality in certain tasks.

We're Humans First

If an alien species arrived tomorrow and examined us, I doubt their first conclusion would be:

"These are clearly two radically different organisms."

They'd probably notice something much more obvious.

Every human has nearly the same fundamental architecture.

We communicate using language.

We form relationships.

We cooperate.

We compete.

We create societies.

We build tools.

We experience fear.

We experience attraction.

We experience jealousy.

We experience curiosity.

We want status.

We want belonging.

We get lonely.

We learn.

We remember.

We imagine futures that don't exist.

And somehow billions of us have convinced ourselves that variations inside this shared system divide humanity into two psychologically uniform teams.

Individual > Category

Biological categories are useful.

Population averages are useful.

Statistics are useful.

But when dealing with an individual human being, the individual usually contains much more information than the category.

If I want to know whether someone is strong:

measure their strength.

If I want to know whether they're intelligent:

evaluate their reasoning.

If I want to know whether they're ambitious:

look at their behavior.

If I want to know whether they're kind:

watch how they treat people.

If I want to know whether they're technically capable:

look at what they can build.

Sex can sometimes shift probabilities.

It doesn't write the entire person.

Maybe We're Focusing on the Wrong Difference

The difference between an untrained man and an elite male athlete can be enormous.

The difference between two men in intelligence, personality, ambition or skill can be enormous.

The difference between two women can be enormous.

Sometimes the variation within a sex is more useful for understanding an individual than simply knowing which sex they belong to.

There are men whose personalities resemble some women more than they resemble many other men.

And vice versa.

Because personality isn't generated by one variable.

Neither is intelligence.

Neither is competence.

Neither is character.

Men and Women Are Different

That's scientifically uncontroversial.

But the more interesting statement is:

We're different versions of something overwhelmingly similar.

Different reproductive systems.

Different average hormone profiles.

Different average body compositions.

Some different physiological characteristics.

Some average behavioral differences that may emerge from complicated interactions between biology and environment.

But underneath all of that:

the same biological machinery,

the same fundamental human needs,

and enormous variation from person to person.

So instead of asking:

"What are men like?"

or:

"What are women like?"

there's often a much more useful question:

"What is this person like?"

Because ultimately I don't interact with averages.

I interact with individuals.

And individuals are far more interesting.