But, it has also become increasingly clear, as I have previously noted, that people vary in persistent, systemic ways that arise early in life and that are uncorrelated with "g" which Steve Hsu likes to call "W."
In his oversimplified equation: "Grades = ability + work ethic = IQ + W"
Work ethic, however, is really a place filler for one or more unknown traits that influence performance after controlling for IQ in academics and a variety of other pursuits. One such W factor was found in dopamine gene variants. A study looking at lawyer practice performance after controlling for grades and LSAT scores has homed in on what seem to me to be several factors, with organization and self-discipline making up one large component, and effectiveness in interpersonal communication and practical judgment, which seem congruent to the idea of emotional intelligence, as another.
Some studies of childhood self-control v. impulsivity seem to buttress the dopamine gene and organization/self-discipline component of W findings.
Children with lower scores (poorer self-control) had poorer health at the age of 32. Their lungs didn’t perform as well. They were more likely to have gum disease, be overweight, or depend on drugs like tobacco, alcohol or cannabis. Among those with the highest levels of self-control, 11% had multiple health problems, compared to 27% of those with the lowest levels.
Those with poorer self-control were also more likely to run into financial or social problems. As teenagers, they were more likely to start smoking, leave school with no qualifications, or have unplanned pregnancies. As adults, they had more credit problems and troubles with money, and fewer tangible assets like a home, savings or a pension. They were more likely to have been convicted of a crime, and their own children were more likely to be raised in a single-parent household. And in fact, their childhood self-control was a better predictor of these financial worries than either their IQs or social backgrounds. . . . the more self-control people had as children, the better their futures, even for those at the high end of the scale. They also found that children who developed better self-control as they grew up fared better than those who stayed at the same level.
The differences observed in this study were pronounced by age three! But "7 percent of youngsters in the long-term study developed notably better self-control as they got older. Members of this group displayed better health, made more money and had fewer criminal run-ins as adults than would have been predicted by their self-control levels as young children."
The study largely replicates with a different testing methodolgy, the famous marshmallow test of Walter Mischel at Stanford University that demonstrated that a young child's ability to postpone eating a marshmallow in exchange for a reward later predicted a wide variety of lifetime success measures later in life.
W because it is less well defined and may have multiple components, is less well studied than IQ. But, it seems to be something "real" that can influence crime, poverty, health, social class and success in life at all levels. So, it deserves at least as much attention as IQ. For example, we know far less about how strongly W is hereditary than we do about how much IQ is hereditary.
My own sense is that there are probably multiple, independent components to "W" and that an impulsivity/self-control dimension is probably one of the most important components of it. Another big component may be "emotional intelligence" or "empathy" or "interpersonal skills" or something along that line. There are probably one or two other significant components as well - perhaps creativity, perhaps some other traits.
The impulsivity/self-control component of "W" seems to have some similarity to traits in the Five Factor Personality Model, particularly conscientiousness as:
A considerable amount of research indicates that conscientiousness is one of the best predictors of performance in the workplace, and indeed that after general mental ability is taken into account, the other four of the Big Five personality traits do not aid in predicting career success.
- per this study.
My sense is that the impulsivity/self-control dimension has a fairly strong hereditary element which may be possible to link to a fairly modest number of gene variations, although there is probably a significant gene x environment component to this as well. Efforts to teach self-control have shown measurable success. I have less intuition regarding the extent to which other components of "W" are hereditary or learned, although a guess of 50% hereditary, in line with the heritability of a great many psychological and personality traits, might be a good starting point for a guess on those.
There is, of course, a considerable literature, on ADHD (which has both a hyperactive-impulsive and an inattention component separately measured and used to determine subtypes of the condition), impulsivity (possibly with three or more distinct subcomponents), a variety of "impulse control disorders," the personality trait of novelty seeking, and a cluster of similar traits in the mental health and psychology literature. There is no doubt overlap between these concepts and the Big Five personality trait conscientiousness.