"My purpose in making an extravagant suggestion is to start a discussion. The problem is so real, and nobody is talking about the solution."
As personal rights and freedoms have expanded during this century, there has been less and less talk about temperament. Throughout most of history, however, people have been regarded less as unique individuals than as variations on a few basic human types. In the fifth century B.C. Hippocrates described four temperaments, which he considered to be linked to various predominant bodily fluids, or humors: the sanguine temperament is optimistic and energetic, the melancholic is moody and withdrawn, the choleric is irritable and impulsive, and the phlegmatic is calm and slow. However quaint this theory may seem, Hippocrates anticipated modern linkages of biochemistry with behavior and astutely described types of people as familiar today as they were in antiquity.
By the 1940s two powerful ideologies diverted scientists' age-old interest in the biological dimensions of personality. First, Freud asserted the overwhelming importance of personal history in determining what his followers called character. Second, revulsion at Nazism's proclamation of inferior and superior genetic types converged with the spread of democratic ideas to focus academe on racial equality and the formative power of environment. Among the few scientists to express interest in temperament was I. P. Pavlov, the dark prince of conditioning, who observed of his dogs that "the final nervous activity present in the animal is an alloy of the features peculiar to the type and of the changes wrought by the environment." "Excitatory," choleric dogs, like Slick Willy, were by nature "pugnacious, passionate, and easily and quickly irritated," while the "inhibitory," or melancholic, animal "believes in nothing, hopes for nothing, in everything he sees the dark side." Of the two stabler sorts that Pavlov observed, one was "self-contained and quiet; persistent and steadfast," and the other "energetic and very productive" but easily bored. Such insights, however, were dwarfed by mountains of literature on what our mothers did to us.
Like the ghost in the machine or the mind in the brain, temperament is best glimpsed in action. To discern it, watch a person communicate, says Hagop Akiskal, the senior science adviser on affective and related disorders at the National Institute of Mental Health: "It's not just a matter of personality but something more basic that has to do with rhythm, reactivity, emotion." Of all species, Homo sapiens has the most feelings. Just as drives such as hunger and sleep are more flexible than reflexes like the eye blink and the knee jerk, emotions, which are physiological as well as psychological events, give us more behavioral options than do drives. Some emotions are so basic and universal that the psychologist Hans Eysenck, a pioneer of the modern biological study of personality, who conducts research in London at the Institute of Psychiatry, believes that they're nothing less than the lowest common denominators of human experience. "We've done our studies in thirty-six countries," he says, "and everywhere we find the same three ways in which behavior can differ." To varying degrees all people express fear, which helps us avoid danger; aggression, which enables us to fight it; and extraversion, or sociability, which enables us to face it with equanimity. Fundamentally, our temperaments are distinguished by the traits of anxiety, irritability, and élan.
That our natures are organized around our habitual reactions to threat has given Philip Gold, a research psychiatrist who is the chief of the neuroendocrinology branch of the NIMH, a "tragic view of the human condition." Physical or emotional, real or perceived, danger lurks everywhere, and from an evolutionary perspective our species' great asset and, sometimes, liability is an extremely sensitive emotional and physiological arousal system that detects and reacts to it. This is the stress, or "fight or flight," response. The stable sorts of people whom modern researchers describe as uninhibited, bold, or relaxed can cope with life's vicissitudes—from a snake in the jungle to a fire-breathing boss—in a manner Gold describes as "philosophical," because their stress response isn't triggered by every little thing and doesn't stay on red alert longer than necessary. These resilient people are innately disposed, Gold says, "to celebrate the beauty of existence and the wonders of an interior life and external connections despite being surrounded by unanswerable questions, ambiguous dilemmas, and the certainty of loss and death."
Those who naturally react to the threatening or the merely unfamiliar with an excess of either the flight or the fight response are in for more trouble. Because their stress response spikes frequently and ebbs slowly, Hippocrates' melancholics, whom scientists now describe as anxious, inhibited, or reactive, are so worn down that they are apt to behave in what Gold calls a depressive way: "Faced with a setback, for example, they say it occurred because they're worthless." To protect themselves, the flight-prone often cultivate an avoidant way of life that worsens their plight. "They're likelier to survive in truly threatening situations," Gold says, "but they have less comfortable lives." Hippocrates' cholerics, like Willy and Burton, respond to stress by going into fight mode. To these people, whom researchers variously call aggressive, impulsive, or irritable, the dark possibility of pain and defeat is so intense, Gold says, "that they can't bear to be accountable for it in a depressive way." Instead they blame it on others, and strike out. Although the bias toward one of these fundamental emotional tones, or temperaments, "has to do with what a person has learned he has to be in order to be loved," Gold says, "it also has to do with genetic factors that biologically predispose him to respond in a certain way to the paradigmatic human situations of pleasure and opportunity, danger and loss." He continues, "In the blood-and-guts world of challenges, these differences in the stress response account for the fundamental parameters of what people are like."