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Cognition and perception

The power of personality

John D. Mayer argues that ‘personal intelligence’ shapes our lives.

17 March 2015

Many moons ago, an unknown sage travelled to the Greek temple at Delphi and inscribed ‘Know yourself’ on a pillar – an act that initiated a discussion about self-understanding that has continued through today. Plato explored the inscription’s meaning in his dialogue Philebus. In it, Plato argued that those without self-knowledge often look ridiculous to others and that powerful people without self-understanding often behave rashly and can harm others as a consequence. Many philosophers were inspired by Plato’s work and sought to understand themselves and to live rational and good lives.

In the 19th century, educated people read about the lives of philosophers to reflect on their own lives and to find guidance for their personal choices. Recently, James Miller, a political scientist, studied a group of 12 philosophers from Socrates to Nietzsche, focusing on how the philosophers’ insights and self-inquiry affected their life choices. In Examined Lives, Miller concluded that the philosophers’ principles often failed to address their circumstances and that more than a few of them were unable to live according to their own strictures (Miller, 2012). Miller began to doubt the virtues of the examined life by the end of his project, regarding the philosophers’ lives with, ‘not just awe and admiration, but also pity, chagrin, and, in a few instances, amused disbelief’.

If philosophers didn’t always guide their lives well by using classical logic and principles, maybe there’s a different kind of reasoning that people use to guide their lives intelligently. Could there be a form of reasoning that expressly concerns an understanding how our overall minds work: an understanding of personality itself?

I’ve labelled the capacity to reason about personality ‘personal intelligence’ (Mayer, 2008, 2014). Because each of us possesses a personality, personal intelligence involves reasoning both about ourselves and about other people.

On the shoulders of giants

Philosophers recognised the value of understanding other people even before they argued for self-knowledge. Two thousand years before Plato, the Egyptian thinker Ptahhotep provided lessons on carefully sizing other people up – including how to read personality traits such as laziness and trustworthiness.

Though Plato, Ptahhotep and other ancient philosophers anticipated the importance of self-knowledge and reading people, they had no experimental methods or mental measures to study how people exercised their skills. When the first psychologists founded the field around 1887 they described their work as investigating mental life. The field’s earliest research focused on the basic functions of sensation, perception and memory. At the same time an interdisciplinary group of thinkers formulated theories of the overall mind – and of self-knowledge. Sigmund Freud sought to increase his patients’ self-awareness by applying new therapeutic techniques to make their unconscious conscious. A half century later, Carl Rogers encouraged his therapy clients to follow their authentic, true selves. Yet Freud, Rogers and other thinkers were limited by the psychological understandings of their times.

In the several decades leading up to 2007, psychologists advanced the field of personality psychology in several key ways that led to a new and more powerful grasp of what personality is. For much of the 20th century personality psychologists were a tribe divided by their different theories: psychologists with allegiance to Freud emphasised the conflicts between our unconscious and conscious mind; behaviourists focused on a person’s acts in preference to their inner states; humanistic psychologists emphasised people’s possibilities for healthy psychological growth. The divergence of opinion suggested that even experts weren’t yet sure about the best ways to read personality.

By 2000 most personality psychologists had put aside such differences and had become actively involved in innovative research that newly informed the field. The American Psychologist, after having published next to nothing about personality for the preceding decade, published two articles on the integration of the field in 2005 and 2006 (Mayer, 2005; McAdams & Pals, 2006).

Also by 2007, psychologists expressed a new confidence that personality was worth studying. Psychologists had been engaged in the ‘person–situation’ debate in the late 20th century. The debate concerned whether personality exerted a meaningful influence over an individual’s life or whether most human behaviour was due to the power of situations. That debate had quietened down leading into 2007. In 2009, Fleeson and Noftle declared that: ‘Instead of fighting over whether to study personality, or what type of personality to study, effort can be placed into actually studying personality’ – as researchers already were doing (Fleeson & Noftle, 2009, p.153).

New findings spelled out how we perceive traits. In the 1980s psychologists attained consensus that everyday traits (represented in the language) could be covered fairly well by five ‘big’ traits of Neuroticism, Openness, Extraversion, Agreeableness and Conscientiousness. As psychologists enlarged their research activities they created encyclopedic collections of statistical data about the relations among those big five (Goldberg et al., 2006). By 2007 a great deal was known about what those traits predicted (Roberts et al., 2007). Psychologists also synthesised hierarchies of defence mechanisms and explored the influence of defensive distortions on people’s lives (Vaillant, 2000). They further examined how people read one another’s intentions and the best way to formulate goals (Chulef et al., 2001; Emmons & King, 1988).

From 2000 to 2007, psychologists zeroed in on topics especially relevant to understanding ourselves and others: David Dunning, Timothy Wilson and Elizabeth Dunn reviewed the past decades’ work on self-knowledge; David Funder established the Riverside Accuracy Project to understand more about how we read other people accurately (Dunning, 2005; Funder, 2012; Wilson & Dunn, 2004).

These advances were the foundation that made the theory of personal intelligence possible: before psychologists could identify who was genuinely smart about personality, they needed to better understand the logic by which the personality system operates.

What does personal intelligence look like?

Psychologists agree on a definition of personality as a system that represents an individual’s broad psychological functioning. I define personality as the global psychological system that organises a person’s motives and emotions, knowledge and intelligence, expression and action, and self-control and awareness.

Intelligence, meanwhile, is a capacity to solve mental problems. In the Cattell–Horn–Carroll model of intelligence – a prevailing contemporary model – there are three levels of human mental abilities. Think of an organisational chart with the company president at the top, division managers at the second level, and individual staff at the third. In the intelligence model, general intelligence is at the top, broad intelligences occupy the second level, and more specific abilities are at the third.

Each broad intelligence reflects a consequential set of problem-solving abilities. Some of the broad intelligences are content-focused, such as verbal and spatial intelligences, and that’s where I believe personal intelligence fits in. (Other broad intelligences are function-focused, such as memory capacity and speed of mental processing.)

Our reasoning about personality is woven into our daily activities. We think about other people, talk about them, make decisions about them, and reflect on ourselves. As we do, we may discuss our thoughts with others, record our thoughts on Facebook, in e-mails or in a diary. In each instance we leave behind a trace of what we understand about personality. Certain public figures whose lives have been chronicled in autobiography or biography – scientists, artists, leaders and celebrities – often do their thinking about people in public, and their reasoning becomes part of the public record.

For example, traces of personal intelligence run through Katherine Graham’s memoir of her life and leadership of the Washington Post newspaper. Graham took over the paper in the 1970s after the unexpected death of her husband (who was until then the paper’s publisher). Graham described her decision to take over in psychological terms. Although she had never run any business, let alone a large newspaper with multiple media holdings, she felt she couldn’t desert the paper or sell it. She had watched her father and husband build the paper into an influential news source, and was personally motivated to continue their legacy. I believe her journey was guided in part by her ability to see herself and other people accurately.

Before deciding to take the helm of the newspaper herself, Graham consulted with trusted friends, who encouraged her to take on the challenge. In her new role as publisher she understood that the Post staff members would see her in different ways depending upon their own personalities and needs. Many on the staff would view her as a clueless intruder, some would welcome her, and more than a few wouldn’t care that she’d taken over. Sometime after she took control of the paper she also revised her view of her deceased husband. She realised that she had idolised his service as publisher, and concluded that she would both need to become more realistic about his talents and to find her own individual path to leadership. She thought in psychological terms – and with considerable accuracy – about her role as a leader.

Four areas of problem solving

The theory of personal intelligence describes four broad areas in which problem solving about personality occurs. Individuals (1) recognise clues to personality, (2) form models of people, (3) guide choices on that basis, and (4) systematise their goals and plans.

Consider Ben, who went to dinner with his new colleague from work, Aiden. When they met at the restaurant, Ben identified clues to Aiden’s personality: he observed Aiden’s clothes (a rather expensive raincoat), noticed the scowl that seemed set on Aiden’s face; and once they were seated at their table, Ben noticed that Aiden spoke eloquently and seemed to understand what one of their new business clients was looking for with considerable clarity. When Aiden criticised a co-worker, Ben thought it was a bit harsh, but Aiden leavened his comment with the reflection that, ‘we all have our limitations’.

Ben next used the clues he had observed to form a tentative model of Aiden’s personality – that Aiden was a pretty smart guy (based on his facility with the language) who didn’t suffer fools gladly (his scowl, his harsh comments about a colleague), and who coped with his disappointments with philosophical humour.

Ben entered a third phase of problem solving – guiding choices – at the same time. He knew he often liked people such as Aiden, and that they could form a friendly alliance at work if Aiden was like similar people Ben had known in the past.

The final area of personal intelligence – systematising plans and goals – generally takes place over a longer period of time. Ben’s beliefs about Aiden, and his interest in him were part of Ben’s longer-term goals of making friends and excelling on the job.

We all continually engage in this type of problem solving as we encounter new individuals and readjust our relationships with those we know. In these instances, personal intelligence serves as a guidance system to our personalities.

A psychometric test of the concept

It’s one thing to have a theory of personal intelligence and another to collect evidence of its existence. In 2008 I joined with my colleagues David R. Caruso of Yale University and Abigail T. Panter of the University of North Carolina to test the hypothesis that personal intelligence existed.

We created a measure called the Test of Personal Intelligence (TOPI) to search for evidence concerning the theory. The test consisted of 140 questions divided into the four areas of personal intelligence described above – recognising information, forming models, guiding choices and systematising goals. Within each of the four areas were several distinct clusters of items to measure problem solving in that realm.

One way we form models of personality is to notice a key characteristic of a person, and then to anticipate other qualities that often go along with that feature. We can do that because certain traits tend to co-occur more often than others. To measure people’s abilities to form accurate models of people, we asked questions such as:

A person is straightforward and modest. Most likely she also could be described as:
A.    Independent and disagreeable
B.    Active and full of energy
C.    Sympathetic to others and ‘tender minded’
D.    Self-conscious and more anxious than average

The answer to this item is ‘C’ because research indicates that people who are straightforward and modest are also likely to be more tender-minded and sympathetic to others.

Over a series of three studies, we found evidence that people vary reliably in their abilities to solve a diverse group of problems pertinent to understanding personality. Some test-takers performed well across the diverse tasks, whereas others fared more poorly, indicating that people’s performance is due to a broad ability to solve problems in the area – a personal intelligence (Mayer et al., 2012).

The correlations between the Test of Personal Intelligence and other measures also suggested that personal intelligence is a broad intelligence. In our most recent published study, the TOPI correlated significantly with a measure of vocabulary (a proxy for verbal intelligence) and with psychological openness, a common correlate of intelligence. We also found that people who are ‘psychologically minded’ – those who like to access their feelings, discuss problems and figure out others – also tend to be higher in personal intelligence.

What about emotional intelligence?

My colleagues and I view emotional  – the ability to reason accurately about emotion – as an intelligence that is validly measured only by ability measures (Mayer, Roberts et al., 2008; Mayer, Salovey et al., 2008). Other psychologists assess what they call ‘EQ’, ‘mixed models’ or ‘trait ei’ by asking people about their optimism or persistence; we regard that approach as measuring something other than the actual intelligence. The current ability measures of emotional intelligence we use, although imperfect, stand up to considerable scrutiny, with intelligence researchers now arguing that EI could be added to the Cattell–Horn–Carroll intelligence model (MacCann et al., 2014). In my next remarks about personal intelligence and its criterion relations, my reference to tests of emotional intelligence will be limited to the ability model and ability-based measures.

Personal intelligence represents a dramatic broadening of the concept of emotional intelligence. It includes problem solving about motives, traits, goals, and other facets of personality, in addition to thinking accurately about emotions. Few TOPI test items ask anything directly about emotion.

Research in this area is new, but our preliminary findings suggest that high scorers on the Test of Personal Intelligence may experience life advantages specific to having healthier personalities. High scorers on the TOPI lack symptoms of personality disorders, and are higher in conscientiousness – a trait that is increasingly viewed as a global index of the integrity of personality functioning (Mayer et al., 2012, Study 3; Mayer, 2014). People good at problem solving about personality in general also exhibit higher than usual emotional intelligence, as reflected by a high, significant correlation between the TOPI and the combined emotional understanding and emotion management branches of the Mayer–Salovey–Caruso Emotional Intelligence Test (MSCEIT). Whereas the TOPI is related to the big five variable of conscientiousness, however, the MSCEIT’s relationship with the variable appears weaker or non-existent (Brackett & Mayer, 2003; Iliescu et al., 2013; Karim & Weisz, 2010).

Is personal intelligence important?

Personal intelligence is important at both the individual and societal levels. At an individual level, it explains the reasoning we use to understand ourselves and other people and helps to mitigate our ‘blind spots’ – matters we don’t know about ourselves and others. Improving our understanding of ourselves and other people is likely to lead to our enhanced well-being and to smoother relationships with others.

We further use our personal intelligence to inform ourselves about our future – by paying particular attention to people with the same characteristics we have. If I seek constant excitement, then I can use my personal intelligence to identify and track down the class of people who are ‘sensation-seekers’ like me. I’ll learn that I’ll likely enjoy extreme sports, and that I might enjoy work as a firefighter, emergency medical technician or other first responder. On the downside, as a member of the class of sensation-seeking people, I’ll need to manage my risk judiciously. Sensation seekers are more likely than others to take dangerous physical risks and to experiment with and abuse mind-altering drugs.

Turning to the level of society, I believe we need to better acknowledge and respect people who use their personal intelligence well. We benefit not only from the engineers who design our computers, phones and cars, and not only from the farmers who grow our food, but also from people who understand themselves well and interact with others with respect and understanding. Personal intelligence provides recognition to individuals who excel in this area.

The reverse condition also exists. Some people around us are relatively insensitive to the personalities they interact with. In meetings, individuals who are low in personal intelligence may be prone to make insensitive remarks to other group members who sit around the same table. Before we attribute their behaviour to hostility, we should consider that they may say what they do because they lack a basic understanding of people – regardless of how smart they are in other areas.

Tests of personal intelligence will help us identify individuals who are gifted in this area, and those who could benefit from education about personality. Psychotherapists have been helping people improve their capacity to understand personalities since the beginning of the field. Therapists encourage their clients to attend to their own feelings and reactions to the surrounding world – and to think more accurately about what other people are like. We may be at a point where we can supplement such therapy with classes and manuals about personality that will enable us to educate people about how this problem-solving takes place and to strengthen people’s reasoning in the area.

At the outset of this article I described how philosophers valued self-knowledge and yet might not always be good role models in that regard. Part of the trick of getting through life is using the right kind of intelligence for the right job. Schneider and Newman (2014) have pointed out that each broad intelligence, such as verbal or spatial intelligence, makes a different prediction about an individual’s future. For example, people with high spatial intelligence are more likely than others to succeed at such careers as engineering and architecture (Wai et al., 2009). In other words, we apply spatial intelligence to the world of two- and three-dimensional objects and verbal intelligence to the world of thoughts and ideas… and, I believe, we employ a personal intelligence to help us understand our mental lives and the personalities around us.

John D. Mayer is Professor of Psychology at the University of New Hampshire
[email protected]


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