The Evolutionary Basis of Morality

Marc J. Roberts

November 3, 2008

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A Preliminary Warning: “Is Does Not Imply Ought”

• Finding an evolutionary basis for some forms of human behavior DOES NOT mean such behavior is necessarily ethically appropriate

• We act to alter many aspects of “normal” human functioning (e.g. tooth decay or smallpox)

• However understanding the evolutionary basis of our judgments can help us to make judgments about which of those judgments to accept—and why!

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Why Should We Expect Evolution To Have Shaped Human Morality?

• Human beings are social animals• The capacity to cooperate has influenced

past survival• Morality influences the capacity to

cooperate• Evolution has therefore selected our

ancestors for their capacity to cooperate and hence for their moral responses.

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The Interdependence of Culture and Genetics

• “Culture” and genetics can co-evolve• The example of adult lactose tolerance• The advantages of urbanization: economies

of scale, specialized skills and agricultural risk diversification

• The challenges of urbanization—not killing unrelated individuals and engaging in reliable exchange relationships

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Human Beings as “Self Domesticating”

• Group size in hunter-gatherer bands• Male mortality due to violence in such

settings• Trends in violent death among English

males over 500 years• The human pre-frontal cortex as a center of

inhibition

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The Impact of Evolution (1):Intuition, Instinct, Emotion, and Impulse

• Evolution will strongly selected for any behavior with substantial survival value

• We experience those evolutionary consequences as strong, even uncontrollable, impulses and feelings

• These feelings arise rapidly and spontaneously: lust, love, fear, disgust, rage etc.

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The Impact of Evolution (2): Concepts, Theories, and Rules

• The human brain has many evolutionary disadvantages: energy consumption, mechanical support, birth risks, developmental delay

• What are its comparable survival advantages?• “Higher” brain functions involve rules, theories

and concepts that allow for explanation and prediction

• We experience that as “the rage to order”7

Moral Decision Making Reflects Both Components

• Many experimental studies of moral psychology reveal a “two track” decision process

• Moral decisions are often made quickly and without reflection: “X is wrong!”

• Once made, such decisions may be re-considered , rationalized, and (only) occasionally revised based on further reflection

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The “Moral Impulses”

• From Haidt and Gazzaniga– Protect the vulnerable– Be fair: exhibit reciprocity– Favor “us” versus “them”– Respect authority– Pursue “purity” and avoid “impurity”

• Other Candidates– Self preservation/competitive advancement– Avoid killing

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Moral Impulse 1: Avoid Killing

• A predisposition to avoid killing other human beings is extremely valuable in promoting social cooperation

• Ample evidence from the history of war that soldiers –even in combat—act to avoid killing others

• “Dehumanization” of the enemy as a way to neutralize this impulse

• Modern training to kill reflexively and the increase in PTSD

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Moral Impulse 2: Self Preservation and Competitive Advancement

• Clearly favored by “sexual selection” as an evolutionary mechanism

• Not limitlessly powerful: adolescent male risk taking in the context of hunting, exploring and inter-group conflict

• Can be a powerful force for subverting rule-following behavior, e.g. in fostering corruption

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Moral Impulse 3: Pursue Purity

• Haidt argues this is rooted in reactions of “disgust” that are basic and universal

• Rooted in managing excrement (and fecal-oral disease transmission)and avoiding rotten foods

• Has often become intertwined with elaborate (religious)conceptual systems of explanation and guidance e.g. sin as degradation and sainthood as purity

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Moral Impulse 4:Respect Authority

• Rooted in the need for children to listen to their parents in order to survive childhood in a dangerous world

• Like purity, becomes re-processed into larger systems of authority and loyalty, as well as religion (i.e. “God the father”)

• Authority often connected to the legitimacy of punishment/violence and the enforcement of other norms

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Moral Impulse 5: Favor “Us” vs. “Them”

• In-group loyalty is of great value in promoting behavior that advances group survival

• In hunter gatherer bands where most members are at least second cousins, the logic of “kin selection” favors some self-sacrifice

• Cities require “us” to encompass ever more distant relatives—”tribe”, “clan”, “people”: with chief as symbolic “father”

• Contemporary nationalism as the ultimate step—e.g. “mother Russia”

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Moral Impulses 6: Be “Fair” –Exhibit Reciprocity

• Essential to get around the lure of rule-breaking, and “free riders”

• May be the most “advanced” human impulse• Value to communities is clear• Value to individuals through reputation—the moral

centrality of gossip, “indirect reciprocity”, and shunning

• The evolution of blushing and crying , emotional authenticity and the capacity to detect cheaters

• Connected to “us” vs. “them” distinction

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Moral Impulse 7:Protect the Vulnerable

• Consider normal human responses to babies, puppies etc.

• Of obvious value to kin selection in hunter-gatherer context

• The situation of the badly off is less compelling if it is “their fault”—that puts them in another frame

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The Link Between Morality and Religion

• Religion serves many purposes besides communicating morality – Legitimate authority– Explain life, death and bad luck, – Deflect bad luck, – Reinforce solidarity through group activities

(dance, chanting) and distinct beliefs

• Has served to foster supra-tribal identification and more wide-spread reciprocity and rule following

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The Link Between Morality and Politics

• Significant empirical research on this point• Liberals emphasize Haidt’s first two norms:

protect the vulnerable and promote fairness• Conservatives stress authority, group

loyalty and purity

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Implications

• Moral theories reflect the “reasoning” and not the “reacting” aspects of human moral decision making

• Utilitarianism and liberalism represent the elaboration of two specific moral impulses– care and protection on the one hand and fairness on the other

• The movement toward universalism in the last 250 years involves redefining “humanity” as the ultimate “us”

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