The Revival of Human Nature [Not Equal to] the Denial of Human Nurture: Toward a Consilient Science of Human Behavior

Article excerpt

When dealing with biological systems, understanding structure is crucial to understanding function--a view that is completely antithetical to the ... black box approach to brain function. For example, consider how our understanding of the anatomy of the DNA molecule--its double-helical structure--completely transformed our understanding of heredity and genetics, which until then had remained a black box subject. Indeed, once the double helix was discovered, it became obvious that the structural logic of this DNA molecule dictates the functional logic of heredity. (1)

--V. S. Ramachandran [Emphasis added]

... each individual picks and chooses from a range of stimuli and events largely on the basis of his or her genotype and creates a unique set of experiences--that is, people help to create their own environments. This view of human development does not ... minimize the role of learning. Rather, it views humans as dynamic creative organisms for whom the opportunity to learn and to experience new environments amplifies the effects of the genotype on the phenotype. It also reminds us of links to the biological world and to our evolutionary history.... [h]umans have adapted to life in face-to-face groups (sociality). Unraveling the role human individual differences play in evolution ... will turn behavior genetics ... from a descriptive discipline to an explanatory one. (2)

--Thomas Bouchard [Emphasis added]

THESE QUOTATIONS EPITOMIZE a consilient perspective seemingly at odds with the assertions of a strong "blank slate" approach to the study of human behavior, which posits:

* Humans beings come into the world much closer to the blank slate end of the continuum than any other species.

* Most of what humans know or know how to do is not present in any form at birth.

* Many, if not most, of the important similarities and differences in behavior between individuals can parsimoniously be explained due to learning.

The "almost blank" perspective, if taken dogmatically rather than pragmatically, renders itself obsolete by dismissing the vital contributions of evolutionary psychology, behavior genetics, and the neurosciences. A consilient perspective, on the other hand, integrates those disciplines with the psychology of learning. It produces a coherent understanding of human behavior that advances scientific knowledge and fosters the compassionate treatment of real human problems. The revival of human nature is not a denial of human nurture. In this article we shall see why:

* The slates aren't blank.

* They aren't identical.

* They're not even slates.

The Slates Aren't Blank--Evolutionary Psychology

A consilient perspective grows out of Darwin's ideas about the continuity of humans with other species in both body and behavior. As the Sage of Down demonstrated in The Expression of the Emotions in Man and Animals (the natural extension of his earlier work in The Origin of Species and The Descent of Man), natural selection has made certain types of learning easier than others. (4) For example, learning to avoid certain tastes provides a distinct survival advantage. It occurs in many species, from sluggish slugs to wily coyotes. (5) One very exasperating illustration, from the human point of view, is bait shyness in rodents. When a vat eats enough poisonous bait to become nauseous but not enough to die, it associates the illness with the taste of the food rather than the light, sound, location or other stimuli at the scene of the crime. This occurs even if the interval between ingestion and indigestion is much longer than for other stimulus-response conditioning, and it is particularly persistent if the food is unfamiliar.

Evolution has selected for adaptations that allow animals, including humans, to meet the recurrent physical, biological, and social challenges of life. Cognitive modules have evolved to detect the stimuli for longstanding, recurring problems and match them to the appropriate responses. …