Character: What Strengths, Virtues and Grit Research Gets Right and Wrong

Follows: Stoicism for Real Life · Stoicism, Properly: The Discourses, the Meditations, and a Daily Practice · Moral Philosophy, Seriously: The Four Big Theories and Where Each Breaks

In this deep dive

1. From philosophers' virtues to psychologists' strengths
2. What the strengths research gets right, and where it wobbles
3. Grit: a big idea meets a meta-analysis
4. The trait that keeps showing up: conscientiousness
5. The situationist challenge: does character even exist?
6. How the debate settled, more or less
7. How character actually develops

A group of students at a theological seminary are told to walk to another building to give a short talk. Some are told they have plenty of time. Others are told they're already late and should hurry. On the way, each of them passes a shabbily dressed man slumped in a doorway, apparently in need of help.

Half the students have just been asked to prepare a talk on the parable of the Good Samaritan, the story of the traveller who stops for a stranger beaten and left by the road.

Who stops to help? Not, it turns out, the students who were thinking about the Good Samaritan, or the ones who scored as more religious. What mattered most was whether they were in a hurry. Among those with time to spare, 63% offered help. Among those told they were late, 10% did.

That 1973 experiment, by John Darley and Daniel Batson, is one of the reasons some philosophers and psychologists came to doubt that "character," in the sense of a stable, reliable disposition to be honest or kind or brave, really exists. Yet in the same decades, other psychologists were building tools to measure character strengths in tens of millions of people, and researchers were finding that certain traits predict who lives longer, earns more and stays married.

Stoicism for Real Life ended with the Stoic claim that the only true good is virtue: wisdom, justice, courage and self-control. Stoicism, Properly goes back to the Stoics' own texts, and Moral Philosophy, Seriously sets virtue ethics beside the other great moral theories, including a first look at the situationist challenge. This piece asks what happened when psychologists tried to measure it, and what the evidence says about whether character is real, whether it matters, and whether you can change yours.

Part 1 — From philosophers' virtues to psychologists' strengths

For most of history, character was a subject for philosophers and religious teachers. Aristotle's Nicomachean Ethics argued that virtues are stable states of character built by practice, and that each one sits at a sensible middle point between two vices. Courage, for example, sits between cowardice and recklessness. He was blunt about how hard that is:

"Hence also it is no easy task to be good." — Aristotle, Nicomachean Ethics II.9 (trans. W.D. Ross)

The Stoics went further, holding that virtue is the only true good and that a perfectly wise person, the "sage," would be virtuous in every situation. They also thought such a person was vanishingly rare.

The VIA classification

In the early 2000s, two psychologists set out to give character a scientific map. Christopher Peterson and Martin Seligman, a founder of the positive psychology movement, led a three-year project involving 55 scientists, supported by what is now the VIA Institute on Character. The result, Character Strengths and Virtues: A Handbook and Classification (2004), was meant as a positive counterpart to the psychiatric manuals that classify what goes wrong with people.

The team started by reading widely across traditions. In a 2005 paper, Katherine Dahlsgaard, Peterson and Seligman reported that six core virtues kept recurring in the writings of Confucianism, Taoism, Buddhism, Hinduism, Athenian philosophy, Judaism, Christianity and Islam. They then sorted 24 more specific "character strengths" under those six headings.

The VIA Institute offers a free online questionnaire, the VIA Survey, that ranks your 24 strengths from top to bottom. By the Institute's own count, more than 40 million people have taken it.

What was new

Two features made this different from older lists of virtues.

Strengths, not a single standard. Aristotle and the Stoics described one ideal of a good person. The VIA approach assumes that people have different profiles: one person's top strengths might be curiosity and humour, another's kindness and fairness. The practical advice that grew out of it is to identify and use your signature strengths rather than fix your weakest ones.

Measurable, at least in principle. Each strength became a scale, which meant researchers could ask whether strengths predict well-being, whether they differ across countries, and whether they can be changed.

Notice what got lost in the translation. In Aristotle, a virtue is a mean, so too much of something can be a vice. Honesty without tact becomes cruelty, and bravery without judgment becomes recklessness. A ranked list of strengths quietly suggests that more is always better. In 2011, the psychologists Adam Grant and Barry Schwartz argued that psychology had largely ignored these "too much of a good thing" effects, and that Aristotle's idea of the mean might be a useful guide for research. We'll come back to this.

Part 2 — What the strengths research gets right, and where it wobbles

The good news: remarkable agreement across cultures

In 2014, Robert McGrath analysed VIA Survey results from 1,063,921 adults who took it online between 2002 and 2012. Across 75 countries with at least 150 respondents each, people ranked the strengths in strikingly similar orders.

McGrath was frank about the limits. People who choose to take a personality survey online probably aren't representative of their countries. Still, the broad similarity supports the idea that some conception of good character is widely shared.

The low ranking of self-regulation is worth pausing on. Across cultures, people rate themselves least strong on exactly the quality the Stoics and Aristotle thought most essential to building every other virtue.

The wobble: six virtues don't show up in the data

If the six virtues were real psychological categories, strengths in the same group should cluster together statistically. They mostly don't. McGrath noted that factor analyses of VIA-style measures usually find four or five clusters that "do not correspond well to traditional lists of virtues." Using more than a million cases from four samples, he proposed that the data fit three broad virtues better:

1. Caring, roughly concern for other people
2. Inquisitiveness, roughly curiosity and the drive to learn
3. Self-control, roughly restraint and discipline

In his analysis, a single factor for "good character" split first into goodness and inquisitiveness, and goodness then split into caring and self-control.

That doesn't make the classification useless. It means the six virtues are a cultural and philosophical framework laid over the data, not a structure the data produced.

Do strength exercises work?

The most famous test came in 2005. Seligman and colleagues ran a randomised online study comparing five "happiness interventions" with a placebo exercise. Two of the exercises lasted only a week: writing down three good things each day, and using one of your top strengths in a new way each day. Both were reported to have lasting effects, raising happiness and reducing depressive symptoms.

Then came the replications.

• In 2012, Mongrain and Anselmo-Matthews repeated the study with a better control condition, plus a "positive placebo" that had people think about positive things about themselves without doing the strengths exercises. The exercises did raise happiness, but so did the positive placebo, and the exercises did no better than the control on depression. Their conclusion: the benefit may come from simply thinking about good things about yourself, not from the strengths themselves.
• In 2019, White, Uttl and Holder re-analysed two major meta-analyses of positive-psychology exercises and found that many studies were small and that small studies tended to report larger effects. After correcting for that, the effect on well-being was small but real (around r = .10), and the effect on depression was inconsistent.

Strengths exercises seem to help a little, mostly by getting people to think kindly about themselves. That's worth something. It isn't a transformation.

The self-report problem

Almost all of this rests on people describing themselves. Someone who rates themselves high on honesty and kindness is telling you how they see themselves, which overlaps with, but isn't the same as, how they behave when it costs something. The situationist experiments in Part 5 are what happens when you stop asking and start watching.

Part 3 — Grit: a big idea meets a meta-analysis

No character idea of the 2010s travelled further than grit. Angela Duckworth and colleagues defined it in 2007 as "perseverance and passion for long-term goals" and measured it with a short self-report questionnaire about sticking with goals and interests over time.

The original findings

The 2007 paper reported six studies:

• Grittier adults had more education, in two samples (about 1,500 and 690 people).
• Grittier undergraduates at an Ivy League university had higher grades.
• Grit predicted which cadets stayed through the first summer of training at the US Military Academy at West Point, in two classes of about 1,200 and 1,300 cadets.
• Grittier children went further in the National Spelling Bee. A later paper found this was partly because they practised more.

On average, grit explained about 4% of the variation in these outcomes. It was unrelated to IQ but highly correlated with conscientiousness, one of the "Big Five" personality traits. It still added a little predictive power beyond conscientiousness. A shorter eight-item version followed in 2009.

Duckworth's 2016 book Grit reached a huge audience, and educators took up the idea with enthusiasm.

What the meta-analysis found

In 2017, Marcus Credé, Michael Tynan and Peter Harms pooled the grit literature: 88 samples, 66,807 people and 584 effect sizes. Their findings:

On grades specifically, secondary reports of the meta-analysis put the overall grit correlation at about .17, perseverance alone at about .26, and consistency of interest at about .10. In other words, combining a stronger part and a weaker part into one score made the prediction worse than using perseverance alone.

The authors concluded that grit's main value may lie in the perseverance part, and that interventions to boost grit would probably have only weak effects on success. In a 2018 review, Credé went further, arguing that there was no evidence grit is especially responsive to interventions.

Twins and genes

A 2016 study by Rimfeld, Plomin and colleagues tested grit in 4,642 British 16-year-olds (2,321 pairs of twins) alongside the Big Five, and checked how well each predicted their GCSE exam results.

• Personality, mainly conscientiousness, explained about 6% of the variation in grades. Grit added little to that.
• Perseverance of effort and conscientiousness were correlated at .53 on the surface and .86 genetically, largely the same trait.
• Grit was moderately heritable (37% for perseverance, 20% for consistency of interest), like most personality traits.

A 2020 paper by Annette Ponnock and colleagues summed up the concern in its title: "Grit and conscientiousness: Another jangle fallacy." A "jangle fallacy" is giving a new name to an old thing and treating it as a discovery.

What grit gets right

None of this means persistence doesn't matter. It clearly does, and the perseverance part of grit holds up as a modest predictor. Duckworth's work also did something useful: it got schools and parents talking about effort and long-term goals rather than only innate talent.

What it gets wrong is the size of the claim. The "passion" half adds little, the "new trait" is mostly an old one, and the effects are modest rather than decisive. As Resilience: What Decades of Research Actually Show argued, persistence is also only a virtue when the goal is worth it and reachable.

Part 4 — The trait that keeps showing up: conscientiousness

If grit is mostly conscientiousness, what does the research on conscientiousness itself show? It's one of the Big Five personality traits, alongside openness, extraversion, agreeableness and emotional stability. Conscientious people tend to be organised, responsible, hard-working, self-disciplined and careful.

Big outcomes

In 2007, Brent Roberts and colleagues reviewed long-term studies that measured personality, family background (socioeconomic status) and cognitive ability, then followed people to see who died earlier, divorced, or reached higher-status jobs. Their headline: the effects of personality traits on these outcomes were indistinguishable in size from the effects of family background and IQ.

A 2008 meta-analysis by Kern and Friedman pooled 20 samples and found that more conscientious people tended to live longer, with a correlation of about .11. The strongest links were for the "achievement" (persistent, industrious) and "order" (organised, disciplined) facets.

A correlation of .11 sounds tiny, and for predicting any one person's lifespan, it is. But small shifts in risk, repeated across millions of people and decades of habits, add up to a meaningful difference in how many people die early.

Childhood self-control

The most striking evidence comes from the Dunedin study in New Zealand, which has followed about 1,000 children from birth. In 2011, Terrie Moffitt and colleagues reported that self-control measured in childhood predicted their physical health, substance dependence, finances and criminal convictions at 32. The relationship formed a gradient: each step up in childhood self-control went with better adult outcomes, not just a split between the lowest few and everyone else.

Two details make the study unusually convincing. The effects held after accounting for intelligence and social class. And in a separate cohort of 500 pairs of siblings, the sibling with lower self-control did worse, even though both grew up in the same family.

Does it replicate?

Psychology's replication crisis has knocked over many famous findings. Personality-and-outcome links have done well. In 2019, Christopher Soto ran preregistered, large replications (median sample of 1,504) of 78 published links between Big Five traits and life outcomes.

• 87% of the replications were statistically significant in the expected direction.
• The effects were on average 77% as strong as originally reported, a real but modest shrinkage.

Character in the everyday sense, the dull virtues of showing up, following through and keeping things in order, is one of the better-replicated predictors of a good life in psychology.

The double edge

One complication from Resilience: What Decades of Research Actually Show belongs here too. In a 2015 study of rural Black American teenagers, self-control predicted better psychological outcomes across the board. But among those from low-income families, it also predicted faster biological ageing by 22. Self-discipline helps, but when it's spent fighting heavy structural disadvantage, it can carry a physical cost that grades and good behaviour don't show.

Part 5 — The situationist challenge: does character even exist?

Everything so far assumes that people have stable traits that show up across situations. In the second half of the twentieth century, a series of experiments seemed to say that the situation you're in often matters more than who you are.

Children who cheated, sometimes

The first warning came early. In the 1920s, Hugh Hartshorne and Mark May gave large numbers of American schoolchildren chances to lie, cheat and steal in tests, games and classroom tasks, published as Studies in Deceit (1928). Honesty turned out to be surprisingly specific. A child who cheated on one kind of test often didn't cheat on another. There seemed to be at most local consistency, rather than a general trait of honesty.

Milgram

In 1961, Stanley Milgram began his obedience experiments at Yale. Participants were told they were helping with a study of learning and were asked to give increasingly strong electric shocks to a "learner" whenever he made a mistake. The learner was an actor, and the shocks weren't real, but participants didn't know that.

In the first published experiment (1963), 26 of 40 men went all the way to the highest switch, marked 450 volts, despite the learner's protests and his eventual refusal to answer at all. Many showed extreme stress: sweating, trembling and nervous laughter.

Milgram ran many variations, and those matter as much as the headline. When participants watched other "teachers" refuse to continue, only about 10% went to the end. When they watched another teacher go all the way, about 92% did. The same people, in effect, became very different depending on what those around them did.

The Good Samaritan, in a hurry

Darley and Batson's seminary study, described at the start, pushed the point further. Neither preparing a talk on helping strangers nor scoring high on religious measures predicted stopping. Being in a hurry did.

From experiments to philosophy

In 1999, the philosopher Gilbert Harman argued that ordinary belief in character traits might be an example of the fundamental attribution error, the well-documented tendency to explain other people's behaviour by their personality while underrating the power of their situation. In 2002, John Doris's book Lack of Character made a more moderate case: people may have narrow, situation-specific dispositions (honest about money at work, say), but not the robust, across-the-board traits that virtue ethics seems to need. Together they launched what's called the situationist challenge to virtue ethics.

If whether you help a stranger depends more on whether you're running late than on your values, what does "a good person" even mean?

But read the fine print on the experiments

Several of the famous studies look shakier now than they did.

• Milgram. Gina Perry, who worked through Milgram's archives, reported that many participants doubted the shocks were real, and that the experimenter sometimes went beyond the scripted prompts to keep people going. Other researchers, notably Alexander Haslam and Stephen Reicher, argue that people continued not out of blind obedience but because they identified with the scientific goals they were told they were serving, a view they call engaged followership. That reading is itself disputed. Still, a partial replication by Jerry Burger in 2006, stopped at 150 volts for ethical reasons, found obedience rates only slightly lower than Milgram's.
• The Stanford Prison Experiment (1971), often taught alongside Milgram as proof that roles turn ordinary people cruel, has been heavily criticised. In 2019, Thibault Le Texier, drawing on the archives and interviews with participants, reported in American Psychologist that the guards had received instructions on how to treat prisoners and that participants were rarely fully immersed. It's best not treated as evidence of anything about character.
• Darley and Batson studied a few dozen seminary students in one setting. It's a vivid demonstration, not a precise estimate.

Part 6 — How the debate settled, more or less

Psychology had its own version of this argument, the person–situation debate, which ran for years in the late twentieth century. Two resolutions have broadly held up.

Averages are stable even when moments aren't

In 1979, Seymour Epstein published a paper whose title captures the first answer: "On predicting most of the people much of the time." One situation is a poor guide to anyone's character. Averaged over many situations, behaviour becomes much more predictable.

Here's why, in miniature. Imagine judging someone's kindness from one encounter, when they might be tired, rushed or distracted. Now imagine judging it from a hundred encounters. The noise from any one moment averages out, and the underlying tendency shows through.

In 2001, William Fleeson confirmed this with experience-sampling studies, in which people repeatedly reported how they were acting over two to three weeks of everyday life. Two findings sat side by side:

• Within a person, behaviour varied enormously. The typical individual regularly acted at nearly every level of every trait, from very introverted to very extraverted, depending on the moment.
• The averages of those distributions were almost perfectly stable, and differed reliably between people.

So the situationists were right that single situations swamp traits. The trait psychologists were right that traits are real, as averages. Both can be true, and the life-outcome research in Part 4 shows that the averages matter.

What this means for virtue

Defenders of virtue ethics have several replies, each with its own strongest form.

Virtue was always rare. Aristotle said being good is "no easy task," and the Stoics thought the sage almost nonexistent. Finding that most people don't reliably help strangers is what these traditions predicted, not a refutation of them. Virtue is an ideal to grow toward, not a description of the average person.

Most people have mixed traits. The philosopher Christian Miller argues in The Character Gap (2017) that most of us have neither virtues nor vices but mixed character traits: real dispositions that make us helpful in some conditions and not others, honest up to a point. That accepts the experiments while keeping character real.

Situations are part of character. A wise person knows which situations bring out their worst and arranges life accordingly. That's a skill and a virtue in its own right.

The situationist position still has a strong core: our confidence in our own character, and in other people's, is usually too high, and good behaviour depends heavily on context. That's a live, unresolved disagreement in philosophy, and the evidence doesn't force a winner. What it does settle is that character is neither as fixed and reliable as folk wisdom assumes nor as illusory as the strongest situationist claims.

Part 7 — How character actually develops

If character is real but partial, can you build more of it? Aristotle's answer was habit:

"We become just by doing just acts, temperate by doing temperate acts, brave by doing brave acts." — Aristotle, Nicomachean Ethics II.1 (trans. W.D. Ross)

He added that virtues arise "neither by nature, nor contrary to nature": we're built to be able to acquire them, and practice completes them. Modern research supports a surprising amount of this.

Personality changes, on its own and on purpose

Adulthood Isn't the Finish Line noted that people tend to become more conscientious, emotionally stable and socially confident with age, especially between 20 and 40. That's change without trying. The newer question is whether trying works.

• Therapy changes traits. In 2017, Brent Roberts and colleagues reviewed 207 studies that tracked personality during interventions, mostly therapy, over an average of 24 weeks. Traits changed noticeably (an average effect of about 0.37), mainly emotional stability, then extraversion. The changes persisted at follow-up and appeared in non-clinical programmes too.
• Doing, not wanting, changes traits. Nathan Hudson and colleagues gave people weekly "challenges," small behaviours matching the traits they wanted to develop. Accepting a challenge did nothing. Actually completing challenges predicted change over 15 weeks. That's Aristotle's habituation in a modern lab.
• A phone app changed traits, and friends noticed. In a 2021 randomised trial published in PNAS, Mirjam Stieger and colleagues gave 1,523 people a three-month smartphone coaching programme. People who wanted to increase a trait reported meaningful change (an effect of 0.52), and friends, family or partners also noticed a smaller but real change (0.35). The changes lasted three months after the programme ended. Observers didn't detect change for people trying to decrease a trait.

Schools can teach some of it

For children, the best evidence comes from social and emotional learning programmes, which teach skills such as managing emotions and getting along with others. A 2011 meta-analysis by Joseph Durlak and colleagues covered 213 school programmes and 270,034 students. Compared with control groups, students improved in social and emotional skills, attitudes and behaviour, and gained 11 percentile points in academic achievement. These programmes don't teach "virtue" by name, but they teach many of the skills underneath it.

Use the situationist lesson in your favour

The experiments in Part 5 are often read as bad news about human nature. Flip them, and they become advice.

The situationists didn't prove character is a myth. They proved it's built partly out of the situations you choose, and choosing them well is part of being good.

Strengths in proportion

Finally, back to Aristotle's mean. If you take a strengths survey, treat your top strengths as starting points, not trophies. Ask where each might tip into excess. Curiosity can become distraction, perseverance stubbornness, kindness people-pleasing. And look at the strengths at the bottom of your list, especially if self-regulation is there. Across 75 countries it usually is, which may explain why the oldest advice about character is about practice rather than talent.

The takeaway

Psychology's attempt to measure character got some things right. People across cultures broadly agree on what good character looks like, and conscientiousness, the plain virtue of following through, predicts health, longevity and work outcomes in findings that mostly replicate. Some things shrank under scrutiny. The VIA's six virtues don't show up as six clusters in the data. Strengths exercises help only a little. Grit turned out to be mostly conscientiousness, with perseverance doing the work and "passion" adding little. The situationist experiments showed that single situations often overpower character, though some of the most famous studies have serious flaws. The best-supported resolution is that character is real as a pattern across many situations, not a guarantee in any one, and that it can be changed through repeated action, much as Aristotle said.

Try this: choose one trait you'd like more of, such as patience, courage or follow-through. For the next four weeks, set yourself one small, concrete "challenge" each week that requires acting that way, write it down, and tick it off only when you've done it, not when you've intended it. At the end, ask someone who knows you well whether they've noticed anything. Then pick one situation that reliably brings out your worst (rushing, a certain group, late nights) and change one thing about it.

A note on strengths tests: the VIA Survey and similar questionnaires are self-descriptions, not diagnoses. They're useful prompts for reflection, but a ranking of your strengths isn't a measure of your worth or a verdict on your character.

Sources & Further Reading

Sources
- Aristotle, Nicomachean Ethics, Book II, chapters 1 and 9, trans. W.D. Ross (public domain; MIT Internet Classics Archive).
- Peterson, C. & Seligman, M.E.P. (2004). Character Strengths and Virtues: A Handbook and Classification. Oxford University Press / APA. VIA Institute on Character, "About" page (55-scientist, three-year project; over 40 million survey takers) and "Character Strengths" page (the 24 strengths and six virtues).
- Dahlsgaard, K., Peterson, C. & Seligman, M.E.P. (2005). Shared virtue: The convergence of valued human strengths across culture and history. Review of General Psychology, 9(3).
- McGrath, R.E. (2014). Character strengths in 75 nations: An update. Journal of Positive Psychology. McGrath, R.E. (2015). Integrating psychological and cultural perspectives on virtue: The hierarchical structure of character strengths. Journal of Positive Psychology, 10(5).
- Grant, A.M. & Schwartz, B. (2011). Too much of a good thing: The challenge and opportunity of the inverted U. Perspectives on Psychological Science, 6(1).
- Seligman, M.E.P., Steen, T.A., Park, N. & Peterson, C. (2005). Positive psychology progress: Empirical validation of interventions. American Psychologist, 60(5). Mongrain, M. & Anselmo-Matthews, T. (2012). Do positive psychology exercises work? A replication of Seligman et al. (2005). Journal of Clinical Psychology, 68(4). White, C.A., Uttl, B. & Holder, M.D. (2019). Meta-analyses of positive psychology interventions: The effects are much smaller than previously reported. PLOS ONE, 14(5).
- Duckworth, A.L., Peterson, C., Matthews, M.D. & Kelly, D.R. (2007). Grit: Perseverance and passion for long-term goals. JPSP, 92(6). Duckworth, A.L. & Quinn, P.D. (2009). Development and validation of the Short Grit Scale. Journal of Personality Assessment, 91(2).
- Credé, M., Tynan, M.C. & Harms, P.D. (2017). Much ado about grit: A meta-analytic synthesis of the grit literature. JPSP, 113(3), 492–511 (ρ values as reported in secondary sources: Huang et al., 2025, Journal of Intelligence, 13(1), 11; Rost & Feng, 2024, Behavioral Sciences, 14(1), 40). Credé, M. (2018). What shall we do about grit? Educational Researcher, 47(9).
- Rimfeld, K., Kovas, Y., Dale, P.S. & Plomin, R. (2016). True grit and genetics: Predicting academic achievement from personality. JPSP, 111(5). Ponnock, A. et al. (2020). Grit and conscientiousness: Another jangle fallacy. Journal of Research in Personality, 89.
- Roberts, B.W., Kuncel, N.R., Shiner, R., Caspi, A. & Goldberg, L.R. (2007). The power of personality. Perspectives on Psychological Science, 2(4). Kern, M.L. & Friedman, H.S. (2008). Do conscientious individuals live longer? A quantitative review. Health Psychology, 27(5).
- Moffitt, T.E. et al. (2011). A gradient of childhood self-control predicts health, wealth, and public safety. PNAS, 108(7).
- Soto, C.J. (2019). How replicable are links between personality traits and consequential life outcomes? The Life Outcomes of Personality Replication Project. Psychological Science, 30(5).
- Miller, G.E., Yu, T., Chen, E. & Brody, G.H. (2015). Self-control forecasts better psychosocial outcomes but faster epigenetic aging in low-SES youth. PNAS, 112(33).
- Hartshorne, H. & May, M.A. (1928). Studies in the Nature of Character, Vol. I: Studies in Deceit. Macmillan, as summarised in Peels, R. (2023), Review of Philosophy and Psychology, and Fair & Fasko (2025), Journal of Intelligence.
- Milgram, S. (1963). Behavioral study of obedience. Journal of Abnormal and Social Psychology, 67(4). Variation rates (about 10% and 92%) as reported in Bocchiaro, P. & Zimbardo, P. (2017), On the dynamics of disobedience, Psychology Research and Behavior Management, 10. Burger, J.M. (2009). Replicating Milgram: Would people still obey today? American Psychologist, 64(1).
- Perry, G. (2013). Behind the Shock Machine, as summarised in Lönnqvist, J.-E. (2026), Manufacturing pessimism, Perspectives on Psychological Science, and Grzyb, T. & Doliński, D. (2025), Frontiers in Psychology. Haslam, S.A., Reicher, S.D., Millard, K. & McDonald, R. (2015). "Happy to have been of service." British Journal of Social Psychology, 54(1); for a critique of engaged followership see Grzyb & Doliński (2025).
- Darley, J.M. & Batson, C.D. (1973). "From Jerusalem to Jericho": A study of situational and dispositional variables in helping behavior. JPSP, 27(1).
- Le Texier, T. (2019). Debunking the Stanford Prison Experiment. American Psychologist, 74(7).
- Harman, G. (1999). Moral philosophy meets social psychology: Virtue ethics and the fundamental attribution error. Proceedings of the Aristotelian Society, 99. Doris, J.M. (2002). Lack of Character: Personality and Moral Behavior. Cambridge University Press. Miller, C.B. (2017). The Character Gap: How Good Are We? Oxford University Press.
- Epstein, S. (1979). The stability of behavior: I. On predicting most of the people much of the time. JPSP, 37(7). Fleeson, W. (2001). Toward a structure- and process-integrated view of personality: Traits as density distributions of states. JPSP, 80(6).
- Roberts, B.W. et al. (2017). A systematic review of personality trait change through intervention. Psychological Bulletin, 143(2). Hudson, N.W., Briley, D.A., Chopik, W.J. & Derringer, J. (2019, online 2018). You have to follow through: Attaining behavioral change goals predicts volitional personality change. JPSP. Stieger, M. et al. (2021). Changing personality traits with the help of a digital personality change intervention. PNAS, 118(8).
- Durlak, J.A. et al. (2011). The impact of enhancing students' social and emotional learning: A meta-analysis of school-based universal interventions. Child Development, 82(1).

Go deeper
- 📘 The Character Gap: How Good Are We? — Christian B. Miller (2017). A short, fair-minded philosopher's tour of the experiments in Parts 5 and 6, and the clearest case for "mixed traits."
- 📘 Grit — Angela Duckworth (2016). Read it for the case for effort and long-term goals, then read Part 3 of this piece for the size of the effects.
- 📘 Lack of Character — John M. Doris (2002). The strongest philosophical statement of the situationist challenge. Academic but readable.
- 📘 Nicomachean Ethics — Aristotle, Books II–III. The original theory of virtue as habit and the mean; free in the W.D. Ross translation.
- 🌐 VIA Institute on Character. Take the free survey as a reflection prompt, not a verdict, and compare your bottom five with the 75-nation pattern above.
- 🌐 See also, in this library: Stoicism for Real Life, Stoicism, Properly, Moral Philosophy, Seriously, Adulthood Isn't the Finish Line, Self-Discipline Without Self-Hate (earlier in this series, on willpower and self-control), and next in this series, The Long Game: Designing a Life Across Decades.