Every society likes to flatter itself with the idea that humans are naturally good. We teach children that kindness is instinctive, that cooperation comes easily, that cruelty is an aberration. But history, psychology, and even biology tell a darker story. Humans are not naturally good. We are naturally self-interested—and when goodness stands in the way of self-interest, people almost always choose evil.

This is not to say that cruelty itself is the goal. Most people do not wake up eager to inflict suffering. But when faced with a choice between an honest but difficult path and a dishonest shortcut, between fairness that costs something and injustice that pays, the calculation is almost always the same: What’s in it for me?

And more often than not, the path to “me” runs through someone else’s pain.

Expedience Over Virtue

Evil is tempting not because it is glamorous, but because it is effective. It gets results quickly, decisively, brutally.

• Tyrants maintain power with fear, not kindness. Fear is reliable; kindness is conditional.
• Revolutions that start with noble ideals often descend into bloodshed, because killing rivals is faster than persuading them.
• Corporations and governments alike bend rules, exploit workers, or poison environments because the cost savings and profits are immediate, while the moral costs are distant and diffuse.

Even in everyday life, the pattern holds. Lying on a résumé, cheating on taxes, gossiping about a coworker—these are small evils chosen because they deliver quicker personal benefits than honesty or restraint.

Goodness is harder. It requires patience, sacrifice, and trust in long-term rewards. Evil, by contrast, pays out today.

The Psychology of the Shortcut

The great experiments of modern psychology lay bare how ordinary people slide into evil when it secures their interest.

• In Milgram’s obedience studies, participants delivered what they thought were lethal shocks not out of sadism, but because obeying authority kept them safe from blame. Cruelty became the path of least resistance.
• In the Stanford Prison Experiment, “guards” humiliated “prisoners” not to indulge in evil for its own sake, but because asserting dominance reinforced their own power and status.
• In countless group studies, people side with in-groups against outsiders, even when it requires harming the innocent, because loyalty protects their belonging.

The lesson is simple: people bend morality when self-interest demands it. And it doesn’t take much.

The Biology of Advantage

Evolution offers the ultimate proof. Natural selection did not reward goodness; it rewarded effectiveness. Aggression, deception, and exclusion often kept early humans alive. Altruism evolved too, but it was narrow and strategic—mostly reserved for kin and allies. “Goodness for all” was never a survival strategy. What endured was a selective morality: protect your own, exploit the rest.

That blueprint still runs through our nervous systems today. Empathy exists, but it is selective and fragile. Fear, aggression, and dominance are much stronger motivators when self-interest is on the line.

Why Societies Must Enforce Goodness

If humans naturally chose good, we would not need laws, religions, or reputational systems. But we do—because self-interest alone tends toward cruelty. Civilizations are built not to elevate our virtues, but to chain our vices. Laws create punishments that make honesty cheaper than fraud. Religions promise eternal damnation to make kindness feel safer than cruelty. Social norms impose shame so that goodness appears less costly than evil.

Remove those guardrails, and human behavior slides back into Hobbes’s “nasty, brutish, and short” state. Without consequences, evil becomes not just an option, but the most rational choice.

The Hard Core of the Matter

The most unsettling truth about human nature is not that people love evil, but that people will choose it—again and again—when it advances their self-interest. We are not saints shackled by occasional temptation. We are self-interested creatures, constantly weighing cost against benefit, and usually choosing whichever path serves us best. Too often, that path is dark.

The hope of civilization, then, is not to change human nature, but to channel it. To make goodness practical. To make cruelty expensive. To build systems where self-interest aligns with decency, so that choosing “good” finally pays more than choosing “evil.”

Because left to our own devices, we already know which path we’ll take. And it won’t be the virtuous one.