What science reveals about the benefits of positive thinking
Henry Ford famously noted, “Whether you think you can do it or not, you are usually right.” His point was that beliefs, especially about our talents, performance, and even luck, can be self-fulfilling. Irrespective of whether they are right or wrong, they will become true by influencing objective success outcomes.
Ford was hardly alone. Along the same lines, decades of psychological research show that beliefs matter, often profoundly so. Perhaps the most influential work comes from Albert Bandura’s theory of self-efficacy, defined as people’s beliefs in their capability to organize and execute the actions required to manage prospective situations. Across hundreds of studies, higher self-efficacy has been linked to greater motivation, resilience, learning, and performance. People who believe they can improve are more likely to set challenging goals, invest effort, persist in the face of difficulty, and recover from failure.
Closely related ideas emerged from attribution theory and expectancy value models, which showed that individuals who attribute success to effort rather than fixed ability, and who believe their actions will make a difference, tend to perform better in school and at work. The most popular variant of these, at least in the world of HR and management, has been Carol Dweck’s research on growth versus fixed mindsets, which popularized the idea that believing that abilities can be developed encourages learning-oriented behavior, greater perseverance, and better responses to feedback.
Taken together, this body of research persuaded a large number of people of the importance of mindset, implying a counterintuitive causal chain whereby beliefs shape performance—rather than the other way around. Specifically, the story goes, irrespective of how rational our thoughts are, they will likely shape attention, effort, emotional reactions, and behavior, which in turn impacts tangible results and outcomes.
A mental software update
Suitably, much of the self-help industry has run with this idea at full speed. Bookstores, podcasts, LinkedIn feeds, and corporate off-sites are now saturated with advice urging us to “reframe,” “manifest,” “believe harder,” and “upgrade our mindset.” According to this logic, success is largely a mental software update away. Change your thoughts, and the universe will follow!
This is where things start to get a little silly. Mindset does not suspend physics, probability, or competence. It still matters whether you can actually cross the road without getting hit by a bus. And even if you firmly believe you are Serena Williams on the tennis court, lacking the ability to play tennis means you may be the only person on earth who shares that belief. Confidence does not magically produce a serve, a backhand, or a Grand Slam title.
Motivational cosplay
At its most extreme, mindset culture drifts into motivational cosplay: people repeating affirmations in the mirror while ignoring the inconvenient details of skill, preparation, competition, and luck. Worse, it can quietly turn failure into a moral flaw. If you didn’t succeed, you must not have believed enough, visualized hard enough, or optimized your morning routine sufficiently. Structural barriers, unequal opportunities, and plain bad luck are written out of the story.
The irony is that the science never claimed mindset was omnipotent. Beliefs help when they are tethered to reality. They amplify effort, persistence, and learning, but they cannot substitute for ability, practice, or opportunity. Positive thinking works best when paired with negative feedback, deliberate practice, and a sober assessment of constraints.
In short, mindset matters (a bit), but not in the magical way the self-help industry sells it. Thinking you can do something helps you try. It does not guarantee you will succeed. And no amount of positive thinking will turn wishful confidence into world-class talent.
Modest effects
Indeed, a closer look at the scientific evidence indicates that popular interpretations on the power of mindset and positive thinking have gone too far.
First, the effects of mindset are actually not that large. Meta-analyses show that growth mindset interventions produce small to moderate effects, particularly when compared with structural factors such as prior ability, socioeconomic status, quality of instruction, or access to opportunity. Put differently, believing you can improve is helpful, but it is no substitute for actually improving. Between thinking you are as good as Lionel Messi and being half as good as him, the latter is unequivocally preferable—unless your goal is to impress people who don’t understand soccer, in which case you can hope to deceive or fool them! Confidence without competence may feel empowering, but it rarely wins matches, promotions, or championships. (It does make for popular sitcom characters like Michael Scott or David Brent, though.)
Second, beliefs do not operate in a vacuum. Confidence helps most when it is paired with real skills, feedback, and environments that reward effort. The problem with overvaluing confidence or self-belief is that, roughly half the time, it is correlated with actual ability. When people are genuinely competent, their confidence is often earned, which is why Muhammad Ali could plausibly claim that “it isn’t bragging if you can back it up.” In those cases, belief is less a psychological trick than a reasonably accurate signal of underlying skill.
The trouble starts when confidence drifts away from competence. Underconfidence, while uncomfortable, can be oddly functional: It pushes people to prepare more, seek feedback, and close gaps they suspect (or know) they have. Accurate confidence, by contrast, reflects self-awareness—a realistic calibration between what one can do and what the situation demands. Delusional confidence is different altogether. It may help people impress, persuade, or temporarily fool others, but this is usually a short-lived strategy unless everyone else is equally deluded. When confidence consistently outruns competence, the cost is eventually paid, either by the individual when reality catches up or by everyone else who has to deal with the consequences.
Third, an excessive focus on mindset risks slipping into a form of psychological moralizing, where success is credited to the “right attitude” and failure is blamed on the individual’s thinking rather than on constraints, inequality, or bad luck. This becomes especially problematic when people are encouraged to believe not only that they live in a meritocracy, but also that their outcomes hinge primarily on how strongly they believe in themselves. In such a world, effort and optimism are not just virtues but moral obligations, and when success does not materialize, the only plausible culprit left is the self.
The result is a quiet but corrosive form of self-blame. If belief is supposed to be the main lever of success, then failing to succeed feels like a personal deficiency of character, motivation, or mental toughness. Structural barriers fade into the background, while disappointment is internalized as guilt. Ironically, this narrative can be demotivating, not empowering.
A better way
A more helpful alternative would be to focus less on upgrading people’s beliefs and more on developing their actual skills and competence. This remains valuable even when individuals start out with low confidence in their abilities, which may simply reflect an accurate awareness of the gap between their current and ideal selves. Closing that gap through practice, feedback, and learning does more for long-term performance and well-being than insisting people feel confident before they have much to be confident about.
Needless to say, there is also evidence that positive beliefs can backfire when they become detached from reality. Inflated self-beliefs are linked to poor calibration, overconfidence, and reckless decision-making. In organizational settings, confidence without competence can be costly, especially when it crowds out learning, dissent, or accurate self-assessment.
In some cases, acknowledging that you are simply not very good at something is not an act of pessimism but of strategic realism. Persisting in a poorly matched role or career path on the basis of “false hope” can be actively harmful. Psychologists refer to this as false positive self-beliefs or miscalibrated optimism (which appear to be the norm), where individuals overestimate their likelihood of success and continue investing in goals that are unlikely to pay off. By contrast, recognizing limits early allows people to redirect their effort toward domains where their abilities, interests, and opportunities are better aligned.
There is also a social cost to miscalibration. If others realize you are less capable than you believe yourself to be, the reputational penalty is typically higher than if you had reached that conclusion first. Self-awareness signals judgment and maturity; obliviousness signals risk. In practice, what matters most is not how good you think you are, but how good others think you are, because it is other people who allocate opportunities, responsibilities, promotions, and trust.
Ironically, some of the best performers are those who initially underestimate themselves. Mild underconfidence can motivate preparation, learning, and skill acquisition, leading to steady improvement and positive surprises. Conversely, people who overestimate their abilities often stagnate, mistaking confidence for progress and reassurance for feedback. Over time, belief divorced from performance does not just fail to help; it actively prevents development.
The science, then, supports a more nuanced conclusion. Mindset matters, but it is not magic. Beliefs are best understood as enablers rather than engines of success. They help people make use of their abilities and opportunities, but they cannot substitute for them.
And yet, we tend to praise self-belief far more enthusiastically than self-knowledge. Confidence is celebrated as a virtue; realism is often mistaken for negativity. But from the perspective of everyone else, self-knowledge is usually the more valuable trait. Most of us have worked with at least one person who is spectacularly pleased with themselves, modestly competent at best, and blissfully unaware of the gap between the two. Their confidence may be admirable in the abstract, but it is considerably less charming when they are making decisions, leading teams, or presenting their “vision.”
If we evaluated the world from other people’s point of view, we would quickly realize that it is not in anyone’s interest for the unjustifiably confident to succeed because of those very flaws. When people advance on the strength of misplaced self-belief rather than demonstrated competence, the costs are externalized: Colleagues pick up the slack, organizations absorb the damage, and reality eventually intervenes, often expensively.
A healthier mindset, then, is not blind optimism but informed confidence: knowing what you can do, what you cannot yet do, and where your effort will actually pay off. In short, self-belief may feel good, but self-knowledge gets things done.
Reality rewards competence, not confidence. The only role of belief is to signal whether you know the difference.