Positive psychology is a scientific approach to studying what makes life go well — the conditions, experiences, and character traits associated with human flourishing — rather than focusing exclusively on the reduction of mental illness and the correction of dysfunction. It asks not only what is wrong with people and how to fix it, but what is right with them and how to build on it. Since its formal founding in 1998, positive psychology has generated thousands of peer-reviewed studies, influenced clinical practice, corporate consulting, education policy, and military training programs, and sparked a productive debate about the values embedded in the science of human welfare.
Origins: Seligman's Challenge to Psychology
The formal founding of positive psychology is typically dated to 1998, when Martin Seligman delivered his presidential address to the American Psychological Association and argued that psychology had become too narrowly focused on pathology, suffering, and mental disorder at the expense of studying positive human qualities and the conditions that allow people to thrive.
Seligman's critique was institutional as much as scientific. He observed that after World War II, the Veterans Administration and the National Institute of Mental Health made large-scale funding available for research on mental illness, because treating damaged veterans and civilians was the urgent priority. This funding shaped what psychologists studied and which academic careers flourished. By the century's end, there was a vast scientific literature on depression, anxiety, schizophrenia, and trauma, but comparatively little rigorous research on courage, wisdom, gratitude, hope, or love.
Seligman identified three pillars for a renewed psychology: the study of positive subjective experience (happiness, well-being, flow, hope); the study of positive individual traits (character strengths and virtues); and the study of positive institutions — families, schools, workplaces, communities — that enable individuals to flourish. He collaborated with Mihaly Csikszentmihalyi, the Hungarian-American psychologist best known for his theory of flow, on the founding of the field. Their 2000 paper "Positive Psychology: An Introduction" in the American Psychologist is regarded as the field's founding manifesto.
"The good life is using your signature strengths every day to produce authentic happiness and abundant gratification." — Martin Seligman
The field was not without precursors. Abraham Maslow's hierarchy of needs and concept of self-actualization, Carl Rogers's person-centered therapy, and the humanistic psychology movement of the 1950s and 1960s had anticipated many of positive psychology's themes. Seligman's contribution was to insist on the same rigorous empirical standards — randomized controlled trials, validated measurement instruments, replication — that characterized the best clinical psychology research, rather than the qualitative, phenomenological approach of the humanists.
The PERMA Model
PERMA is Seligman's model of well-being, introduced in his 2011 book "Flourish." It represents a significant revision of his earlier work, in which he had argued that well-being was essentially equivalent to happiness. In "Flourish," he argued that this earlier hedonic framework was too narrow and replaced it with five elements:
| Element | Description | Key Theorist/Research |
|---|---|---|
| Positive Emotion | Pleasurable feelings: joy, gratitude, serenity, hope, awe | Barbara Fredrickson — broaden-and-build theory |
| Engagement | Deep absorption in activity; flow state | Mihaly Csikszentmihalyi |
| Relationships | Positive connections with others | Julianne Holt-Lunstad — social connection and longevity |
| Meaning | Belonging to and serving something larger than the self | Viktor Frankl, Robert Emmons |
| Accomplishment | Achievement pursued for its own sake | Various |
P — Positive Emotion encompasses pleasurable emotions including joy, gratitude, serenity, interest, hope, pride, awe, amusement, and love. Barbara Fredrickson's broaden-and-build theory holds that positive emotions are not merely pleasant but functionally important: they broaden momentary thought-action repertoires (making thinking more flexible and creative), and they build lasting personal resources — cognitive, physical, social, and psychological — that outlast the emotion itself. Fredrickson's (2001) meta-analysis across experiments found consistent support for the broadening effect.
E — Engagement corresponds closely to Csikszentmihalyi's concept of flow: complete absorption in an intrinsically rewarding activity, with loss of self-consciousness and distortion of time perception. Unlike positive emotion, which is accessible in retrospect and during experience, engagement is typically noticed only afterward.
R — Relationships reflects Seligman's claim that other people are not merely contributors to positive emotion but intrinsically valuable components of a flourishing life. The Harvard Study of Adult Development, which tracked men from the 1930s onward in one of the longest longitudinal studies in psychology, found that the warmth of relationships was the single strongest predictor of late-life flourishing (Waldinger and Schulz, 2010).
M — Meaning involves belonging to and serving something beyond the self — religious, political, organizational, or familial. Viktor Frankl's "Man's Search for Meaning" (1946), drawing on his experiences as a Holocaust survivor and psychiatrist, argued that the human drive for meaning is as fundamental as any other motivation, and that meaning-making is possible even under conditions of extreme suffering.
A — Accomplishment is the pursuit of achievement for its own sake, independent of whether it generates positive emotion, engagement, or meaning. Some people pursue goals not because they feel happy doing so but because achieving matters to them intrinsically.
This is a significant departure from hedonic well-being research — the study of subjective happiness associated with Ed Diener's Satisfaction with Life Scale — and from earlier positive psychology frameworks. PERMA explicitly rejects the reduction of well-being to any single dimension.
Flow Theory
Flow is the state of optimal experience studied by Mihaly Csikszentmihalyi (pronounced approximately "Cheeks-sent-me-high"), a Hungarian-American psychologist who developed the concept through decades of research beginning in the 1960s. He described it most fully in his 1990 book "Flow: The Psychology of Optimal Experience."
Flow is the state in which a person is so absorbed in an intrinsically rewarding activity that they lose track of time, forget themselves, and experience the activity as effortless despite full engagement. Csikszentmihalyi initially studied artists, chess players, rock climbers, surgeons, and factory workers — people from very different walks of life who described the same loss of self in their work. The phenomenology of the experience recurred across different activities and cultures.
The key condition for flow is the challenge-skill balance: there must be a match between the difficulty of the activity and the skill level of the person. If challenge significantly exceeds skill, anxiety results; if skill significantly exceeds challenge, boredom results. Flow occurs in the channel between these states, when challenge and skill are well-matched at a level demanding full attention.
"The best moments in our lives are not the passive, receptive, relaxing times... The best moments usually occur if a person's body or mind is stretched to its limits." — Mihaly Csikszentmihalyi
Csikszentmihalyi developed the experience sampling methodology (ESM) — beeping participants at random intervals with a pager (later smartphone) and asking them to report their current activity, thoughts, and emotional state — to study flow and other psychological states in daily life rather than in laboratory settings. This methodology has been widely adopted in psychological research.
Studies using ESM have found that people report higher levels of concentration, engagement, and satisfaction during activities that produce flow states. Paradoxically, people in flow during work activities sometimes report higher well-being than during passive leisure, even though they rate leisure as preferable in the abstract.
Character Strengths and the VIA Classification
The Values in Action (VIA) classification of character strengths, developed by Martin Seligman and Christopher Peterson and published in "Character Strengths and Virtues: A Handbook and Classification" (2004), is a systematic taxonomy of positive personality traits conceived explicitly as a "positive DSM" — a counterpart to the Diagnostic and Statistical Manual that catalogued human weaknesses.
Seligman and Peterson reviewed virtue traditions across world cultures — Greek philosophy, Confucian thought, the Bhagavad Gita, the Bushido code, the Torah, the New Testament, Quaker traditions, and others — looking for traits that appeared consistently across time and culture. From this review, they identified 24 character strengths organized under six broad virtues:
| Virtue | Character Strengths |
|---|---|
| Wisdom | Creativity, curiosity, judgment, love of learning, perspective |
| Courage | Bravery, perseverance, honesty, zest |
| Humanity | Love, kindness, social intelligence |
| Justice | Teamwork, fairness, leadership |
| Temperance | Forgiveness, humility, prudence, self-regulation |
| Transcendence | Appreciation of beauty, gratitude, hope, humor, spirituality |
The VIA Survey, a freely available self-report questionnaire, has been completed by millions of people worldwide and provides a profile of an individual's "signature strengths" — the strengths that feel most authentically one's own. Research by Park and Peterson (2009) found that signature strength use predicts life satisfaction and work engagement above and beyond other predictors.
Cross-cultural validation studies have found that the 24 strengths are recognizable across many cultures, though their relative prevalence and cultural valuation varies. Gratitude, hope, love, curiosity, and zest consistently emerge as the most commonly endorsed strengths globally.
Hedonic Adaptation and the Set Point Theory
Hedonic adaptation is the well-documented process by which people return to a relatively stable level of subjective well-being following major positive or negative life events. Philip Brickman and Donald Campbell's 1971 paper introduced the concept of the hedonic treadmill: because we adapt to improvements in our circumstances, we must continually achieve more to maintain the same level of satisfaction, implying that objective improvements in life conditions produce diminishing marginal returns on subjective happiness.
Brickman, Coates, and Janoff-Bulman's landmark 1978 study compared lottery winners, paraplegics, and a control group. The findings were striking: lottery winners were not significantly happier than controls, and paraplegics, while less happy than controls, reported levels of happiness far higher than controls predicted. Both groups had adapted substantially to their changed circumstances.
David Lykken and Auke Tellegen's set point theory (1996), drawing on twin studies, argued that approximately 50 percent of the variance in subjective well-being is attributable to genetic factors, and that people have a genetically determined baseline to which they reliably return after perturbation. Circumstances accounted for only about 10 percent of variance in their analyses.
Daniel Gilbert's "Stumbling on Happiness" (2006) popularized research on affective forecasting — predictions of how future events will make us feel — showing that people systematically overestimate the emotional impact of both good and bad future events because they underestimate hedonic adaptation. We predict that winning the lottery or becoming paralyzed will permanently transform our happiness level; the evidence suggests adaptation is far more powerful than we expect.
However, Bruce Headey's 2010 long-term panel study challenged the strict set point model, showing that a substantial minority of people demonstrate lasting changes in well-being over decades. Particular life choices — stable partnerships, volunteering, prioritizing altruistic rather than hedonistic goals — appeared associated with lasting upward shifts in well-being, suggesting that the set point is a tendency rather than an immutable destiny.
Gratitude Research
Gratitude research has been one of the most active areas in positive psychology, generating both enthusiasm and methodological scrutiny. Robert Emmons and Michael McCullough's (2003) randomized controlled trial, one of the field's most-cited studies, found that participants assigned to write weekly about things they were grateful for reported higher well-being and fewer physical symptoms compared to those who wrote about daily hassles or neutral events after ten weeks.
This finding spawned a large industry of gratitude interventions in positive psychology and clinical practice. However, subsequent attempts to replicate and extend the original findings have yielded mixed results. A 2016 meta-analysis by Wood and colleagues found that gratitude interventions did produce significant effects on well-being, but with modest effect sizes (d = 0.31 on average) that tended to be smaller in more rigorously controlled studies. Pre-registered replications have been more conservative in their findings than the original research, consistent with the broader replication challenges in social psychology.
Dispositional gratitude — measured as a stable trait rather than assessed after an intervention — shows more robust associations with well-being. McCullough, Emmons, and Tsang (2002) found that grateful people report higher positive affect, more satisfaction with life, more vitality and optimism, and lower levels of envy and depression, though the cross-sectional design limits causal inference.
Criticisms of Positive Psychology
Positive psychology has attracted sustained criticism from multiple directions, representing some of the field's most productive intellectual debates.
The replication problem: The field attracted early attention through studies suggesting that simple interventions — gratitude letters, counting blessings, performing acts of kindness — produced significant and lasting improvements in well-being. Some of these findings have not replicated reliably in pre-registered, adequately powered studies. Effect sizes in positive psychology interventions have generally been smaller in more rigorous subsequent studies. The positive psychology replication crisis is part of the broader reproducibility crisis in social psychology identified by the Open Science Collaboration (2015).
Toxic positivity: Barbara Ehrenreich's "Bright-Sided: How Positive Thinking is Undermining America" (2009) argued that the cultural emphasis on positive thinking and happiness can function as a form of victim-blaming — implying that people who are unhappy lack the right mental attitude rather than facing genuinely difficult material circumstances. Ehrenreich documented how positive thinking ideology in American corporate culture can discourage legitimate criticism of working conditions, and how cancer patients are sometimes pressured to maintain positive attitudes in ways that deny the reality of their situation.
Cultural specificity: Sociological and cultural critics have questioned whether positive psychology's constructs are genuinely universal or culturally specific ideals reflecting Western, individualist, affluent values. The PERMA model's emphasis on individual achievement, personal meaning, and self-determined engagement may not map onto collectivist cultures where self-enhancement is less valued, or onto communities facing structural inequality, poverty, or systemic discrimination.
The negativity bias problem: Critics including Paul Rozin and Ed Royzman have pointed out that the asymmetry between negative and positive experience — the well-documented fact that bad events have stronger and more lasting effects than equivalently good ones — means that a psychology that ignores the negative is necessarily incomplete, regardless of its practical motivation.
"Not everything that can be counted counts, and not everything that counts can be counted." — William Bruce Cameron (often misattributed to Einstein)
Practical Applications
Despite methodological debates, positive psychology has influenced several domains:
Clinical practice: Positive psychotherapy (Seligman, Rashid, and Parks, 2006) incorporates building positive emotion, engagement, and meaning alongside traditional symptom reduction. In randomized trials, it has shown effects on depression comparable to traditional therapies. Well-being therapy developed by Fava and Ruini (2003) specifically targets the six dimensions of psychological well-being identified by Carol Ryff as a complement to symptom-focused treatment.
Education: The Penn Resiliency Program and related social-emotional learning curricula based on positive psychology principles have been implemented in thousands of schools. Meta-analyses by Durlak and colleagues (2011) found that social-emotional learning programs produced an average 11-percentile-point improvement in academic achievement alongside reductions in problem behavior.
Organizational settings: The PERMA-Lead model and related frameworks have been applied to workplace well-being programs. Meta-analyses of workplace well-being interventions report moderate effect sizes, though effect sizes are generally larger in less rigorously controlled studies.
Military psychology: The US Army's Comprehensive Soldier and Family Fitness program, developed in collaboration with Seligman's team at the University of Pennsylvania, was implemented across the entire US Army between 2009 and 2011 in what remains one of the largest applications of positive psychology anywhere. Evaluations found modest benefits for resilience outcomes, though the program's mandatory nature and the scale of implementation complicated evaluation.
Positive psychology's most enduring contribution may not be any specific intervention but the insistence that the full range of human experience — not only suffering and disorder but also flourishing, meaning, strength, and joy — belongs within the scientific agenda of psychology. Whether or not every specific finding survives replication, the reorientation of scientific attention toward the positive conditions of human life has expanded the discipline in ways that appear likely to prove lasting.
Frequently Asked Questions
What is positive psychology and how did it begin?
Positive psychology is a scientific approach to studying what makes life go well — the conditions, experiences, and character traits associated with human flourishing, rather than the reduction of mental illness or dysfunction. Its formal founding is typically dated to 1998, when Martin Seligman, in his presidential address to the American Psychological Association, argued that psychology had become too narrowly focused on pathology, suffering, and mental disorder at the expense of studying positive human qualities and the conditions that allow people to thrive.Seligman's critique was institutional as much as scientific. He pointed out that after World War II, the Veterans Administration and the National Institute of Mental Health made large-scale funding available for research on mental illness, because treating damaged veterans and civilians was the urgent priority. This funding shaped what psychologists studied and what academic careers were built on. By the end of the 20th century, there was a vast scientific literature on depression, anxiety, schizophrenia, trauma, and other forms of psychopathology, but comparatively little rigorous research on courage, wisdom, gratitude, hope, or love.Seligman argued for three pillars of a renewed psychology: the study of positive subjective experience (happiness, well-being, flow, hope), the study of positive individual traits (character strengths and virtues), and the study of positive institutions (families, schools, workplaces, communities) that enable individuals to flourish. He collaborated with Mihaly Csikszentmihalyi, the Hungarian-American psychologist best known for his theory of flow, on the founding of the field, and their 2000 paper 'Positive Psychology: An Introduction' in the American Psychologist is regarded as the field's founding manifesto.The field was not without precursors. Abraham Maslow's hierarchy of needs and concept of self-actualization, Carl Rogers's person-centered therapy, and the humanistic psychology movement of the 1950s and 1960s had anticipated many of positive psychology's themes. Seligman's contribution was to insist on the same rigorous empirical standards — randomized controlled trials, validated measurement instruments, replication — that characterized the best clinical psychology research.
What is the PERMA model and how does it differ from earlier happiness research?
PERMA is Seligman's model of well-being, introduced in his 2011 book 'Flourish.' It represents a significant revision of his earlier work, in which he had argued that well-being was essentially equivalent to happiness, and that happiness had three components: positive emotion, engagement, and meaning. In 'Flourish' he argued that this earlier model was too narrow and replaced it with five elements.P stands for Positive Emotion: experiencing pleasurable emotions including joy, gratitude, serenity, interest, hope, pride, awe, amusement, and love. These are not merely pleasant but are associated with the 'broaden-and-build' theory developed by Barbara Fredrickson, which holds that positive emotions broaden momentary thought-action repertoires and build lasting personal resources — cognitive, physical, social, and psychological.E stands for Engagement: the experience of being deeply absorbed in an activity, corresponding closely to Csikszentmihalyi's concept of flow. Engagement is characterized by loss of self-consciousness, distortion of time perception, and intrinsic motivation.R stands for Relationships: the centrality of positive relationships to well-being. Seligman argues that other people matter fundamentally — not merely as contributors to positive emotion but as intrinsically valuable components of a flourishing life.M stands for Meaning: belonging to and serving something that you believe is larger than the self, whether religious, political, organizational, or familial.A stands for Accomplishment: the pursuit of achievement for its own sake, independent of whether it generates positive emotion, engagement, relationships, or meaning. Some people pursue goals and accomplish them not because they feel happy doing so but because achieving matters to them.This is a significant departure from hedonic well-being research — the study of subjective happiness as a single variable — associated with Ed Diener's Satisfaction with Life Scale and surveys of subjective well-being. Seligman's PERMA model is explicitly pluralistic, rejecting the reduction of well-being to any single dimension including happiness.
What is flow and when does it occur?
Flow is a state of optimal experience described and studied by Mihaly Csikszentmihalyi (pronounced approximately 'Cheeks-sent-me-high'), a Hungarian-American psychologist who developed the concept through decades of research beginning in the 1960s. He described it most fully in his 1990 book 'Flow: The Psychology of Optimal Experience.'Flow is the state in which a person is so absorbed in an intrinsically rewarding activity that they lose track of time, forget themselves, and experience the activity as effortless despite full engagement. Csikszentmihalyi initially studied artists, chess players, rock climbers, surgeons, and factory workers — people who described losing themselves in their work. The phenomenology of the experience recurred across very different activities and cultures: concentration is intense, irrelevant stimuli drop away from consciousness, self-consciousness disappears, time seems to speed up or slow down, and the activity seems to carry itself forward.Csikszentmihalyi identified a set of conditions that reliably produce flow. Most centrally, there must be a match between the challenge of the activity and the skill level of the person. If the challenge significantly exceeds skill, anxiety results. If skill significantly exceeds challenge, boredom results. Flow occurs in the channel between these states, when challenge and skill are well-matched at a level that requires full attention but is within reach. As skill develops, the same challenge level produces boredom, requiring increasing challenge to maintain flow — a built-in mechanism that pushes people toward mastery.Other conditions include clear goals, immediate feedback, and a sense of personal control over the activity. Flow is more likely when external distractions are minimal and when the person has sufficient skill that basic execution is automatic, freeing attentional resources for higher-level aspects of the activity.Csikszentmihalyi developed the experience sampling methodology (ESM) — beeping participants at random intervals with a pager (later replaced by smartphones) and asking them to report their current activity, thoughts, and emotional state — to study flow and other psychological states in daily life rather than in laboratory settings. This methodology has been widely adopted in psychological research.
What are character strengths and how were they identified?
The Values in Action (VIA) classification of character strengths is a systematic taxonomy of positive personality traits developed by Martin Seligman and Christopher Peterson, published in 'Character Strengths and Virtues: A Handbook and Classification' (2004). It was conceived explicitly as a 'positive DSM' — a counterpart to the Diagnostic and Statistical Manual of Mental Disorders that catalogued human weaknesses — that would catalogue human strengths with the same rigor.Seligman and Peterson reviewed virtue traditions across world cultures — Greek philosophy, Confucian thought, the Bhagavad Gita, the Bushido code, the Torah, the New Testament, Quaker traditions, and others — looking for traits that appeared consistently across time and culture. They also consulted secular guides to character including Benjamin Franklin's Autobiography. From this extensive review, they identified 24 character strengths organized under six broad virtues: wisdom (creativity, curiosity, judgment, love of learning, perspective), courage (bravery, perseverance, honesty, zest), humanity (love, kindness, social intelligence), justice (teamwork, fairness, leadership), temperance (forgiveness, humility, prudence, self-regulation), and transcendence (appreciation of beauty, gratitude, hope, humor, spirituality).The strengths were required to meet several criteria to be included: they had to be morally valued in their own right (not merely as means to other ends), they had to be measurable and distinct from one another, and they had to be present in human beings as dispositional traits rather than momentary states. Peterson and Seligman developed the VIA Survey — a freely available self-report questionnaire — which has since been completed by millions of people worldwide and provides a profile of an individual's 'signature strengths,' the strengths that feel most authentically one's own.Cross-cultural validation studies have found that the 24 strengths are recognizable across many different cultures, though their relative prevalence and the degree to which they are valued varies significantly. This is taken as evidence for the universality of the classification, though critics have pointed out that the cultural review from which the strengths were derived was heavily weighted toward literate, documented traditions that share significant historical influence.
What does research say about hedonic adaptation and the set point theory of happiness?
Hedonic adaptation is the well-documented psychological process by which people return to a relatively stable level of subjective well-being following major positive or negative life events. Lottery winners, after an initial period of elevated happiness, tend to return to roughly their pre-win level of happiness within one to two years. People who sustain serious injuries resulting in paralysis, after an initial period of decreased happiness, also tend to return to levels closer to their pre-injury baseline than most observers would predict.Philip Brickman and Donald Campbell's 1971 paper introduced the concept of the hedonic treadmill: because we adapt to improvements in our circumstances, we must continually achieve more to maintain the same level of satisfaction. This implies that objective improvements in life conditions — wealth, health, achievement — produce diminishing marginal returns on subjective happiness.The set point theory (Lykken and Tellegen, 1996) took this further, arguing on the basis of twin studies that approximately 50% of the variance in subjective well-being is attributable to genetic factors. The implication was that people have a genetically determined 'set point' for happiness to which they reliably return after perturbation. Circumstances (wealth, relationships, location) accounted for only about 10% of variance in well-being in these analyses — surprisingly little.Daniel Gilbert's 'Stumbling on Happiness' (2006) popularized research on affective forecasting — our predictions of how future events will make us feel — showing that people systematically overestimate the emotional impact of both good and bad future events because they underestimate hedonic adaptation. We think winning the lottery or getting cancer will permanently transform our happiness level, but adaptation is powerful.However, Bruce Headey's 2010 long-term panel study challenged the set point model, showing that a substantial minority of people demonstrate lasting changes in well-being over decades, contradicting the strict return-to-set-point prediction. Particular life choices — including stable partnerships, volunteering, and prioritizing altruistic rather than hedonistic goals — appeared associated with lasting upward shifts in well-being. This suggests that the set point is a tendency rather than a fixed destiny, and that some interventions and life choices can produce durable change.
What are the main criticisms of positive psychology?
Positive psychology has attracted sustained criticism from multiple directions, ranging from methodological concerns about specific interventions to broader ideological critiques of what the field's assumptions do and do not acknowledge.The most technically specific critique concerns the replication of positive psychology interventions. The field attracted early attention through studies suggesting that relatively simple interventions — writing gratitude letters, counting blessings, performing acts of kindness — produced significant and lasting improvements in well-being. Some of these findings have not replicated reliably in pre-registered, adequately powered studies. The gratitude intervention research (Emmons and McCullough's influential 2003 RCT found that a weekly gratitude journal produced measurable well-being gains) has yielded mixed results on replication. Effect sizes in positive psychology interventions have generally been smaller in more rigorous subsequent studies than in the original research.The 'toxic positivity' critique, articulated in various forms by critics including Barbara Ehrenreich in 'Bright-Sided: How Positive Thinking is Undermining America' (2009), argues that the cultural emphasis on positive thinking, happiness, and optimism can function as a form of victim-blaming — implying that people who are unhappy lack the right mental attitude rather than facing genuinely difficult material circumstances. Ehrenreich documented how positive thinking ideology in American corporate culture can discourage legitimate criticism of working conditions, and how cancer patients are sometimes pressured to maintain positive attitudes in ways that deny the reality of their situation.Sociological and cultural critics have questioned whether positive psychology's constructs are genuinely universal or are culturally specific ideals reflecting Western, individualist, affluent values. The PERMA model's emphasis on individual achievement and personal meaning, they argue, reflects a particular cultural vision of the good life that does not map straightforwardly onto collectivist cultures in which self-enhancement is less valued, or onto communities facing structural inequality, poverty, or systemic discrimination. Well-being scales validated on Western samples may measure something different when applied cross-culturally.