For decades, the common wisdom has been that youth reigns supreme when it comes to mental agility, problem-solving, and leadership potential. But a groundbreaking study published on October 15, 2025, in the journal Intelligence is turning this assumption on its head. According to research led by Gilles Gignac of the University of Western Australia and Marcin Zajenkowski of the University of Warsaw, people often reach their most complete form of mental and emotional intelligence not in their twenties, but around age 60.
This new perspective is more than a feel-good story for those watching the years tick by. The research tracked a composite index spanning nine core psychological constructs, expanding into 16 dimensions—including intelligence, personality, emotional intelligence, and decision-making skills. The findings suggest that between ages 40 and 65, adults typically exhibit the best mix of intelligence, stability, and decision-making prowess. After the mid-60s, average scores dip, but many individuals remain sharp and capable well into their seventies and beyond.
So, what’s really happening as we age? The study points out that while certain abilities—like processing speed and physical strength—decline steadily after the mid-20s, other capacities such as experience, judgment, and emotional balance continue to improve through midlife. The researchers describe this as the "midlife compensation effect," where the slower, more deliberate thinking of older adults is balanced by their accumulated wisdom and emotional maturity.
Fluid intelligence, the ability to solve novel problems quickly, peaks around age 20 and then gradually wanes. Yet, crystallized intelligence—our store of knowledge and vocabulary—keeps rising until the 60s. Financial literacy, too, continues to improve into the late 60s, and moral reasoning tends to rise through most of adulthood. Emotional intelligence, a crucial trait for navigating complex social situations, climbs through midlife before tapering off. Notably, older adults are about twice as likely as their younger counterparts to avoid the infamous sunk cost fallacy—the tendency to throw good money after bad.
Personality traits also mature with age. Conscientiousness and emotional stability, which are closely linked to career success and life satisfaction, both increase from early adulthood into the 50s and 60s. As Gignac and Zajenkowski’s research reveals, these gains offset the losses in raw cognitive power, resulting in a composite peak of overall functioning near ages 55 to 60.
The real-world implications of these findings are striking. Studies show that people typically earn their highest salaries and reach peak occupational prestige between ages 50 and 55. Political leaders of major countries are most commonly elected in their mid-50s to early 60s. Even in traditional hunter-gatherer societies, hunting success peaks between ages 35 and 50. These patterns align closely with the study’s conclusion that late midlife represents the most favorable window of human functioning.
The researchers arrived at these conclusions by analyzing data from large published studies covering cognitive abilities, personality traits, emotional intelligence, financial literacy, moral reasoning, and other psychological capacities. The data came from diverse sources: cognitive ability data from over 5,000 adults aged 19 to 88, personality data from more than 10,000 Dutch participants tracked over 12 years, emotional intelligence data from 456 adults, and financial literacy data from more than 15,000 Japanese adults. All measures were converted to T-scores for direct comparison, and the results were statistically smoothed to reduce noise.
Two models were used to weigh the different psychological dimensions. The "Conventional" model emphasized traditional cognitive abilities and core personality traits, while the "Comprehensive" model included a broader array of capacities, such as emotional intelligence, financial literacy, moral reasoning, and resistance to decision-making biases. Both models pointed to the same conclusion: the late 50s and early 60s are the high point of human psychological functioning.
Interestingly, the study also notes that the decline in overall functioning after the mid-60s is not uniform. While the average scores dip, individual variation is considerable. Some adults maintain strong performance well into old age, while others experience earlier declines. According to the researchers, "age alone doesn’t determine overall cognitive functioning—evaluations and assessments should focus on individuals’ actual abilities and traits rather than age-based assumptions."
This has important implications for society’s approach to leadership and employment. Despite evidence that people in their late 50s and early 60s may be at their best for complex problem-solving and leadership, older workers often face greater challenges re-entering the workforce after job losses. Structural factors—such as mandatory retirement ages for certain professions and employer perceptions about short-term investment—can shape hiring decisions. For example, the International Civil Aviation Organisation sets a global retirement age of 65 for international airline pilots, and many countries require air traffic controllers to retire between 56 and 60. These age limits are often justified by the high demands on memory and attention required by these jobs.
But history is full of examples that defy the stereotype of youth as the apex of achievement. Charles Darwin published On the Origin of Species at 50. Beethoven, at 53 and profoundly deaf, premiered his Ninth Symphony. In the modern era, Lisa Su, now 55, led Advanced Micro Devices through a dramatic technical turnaround. These stories underscore the study’s message: midlife is not a countdown to decline, but a peak in its own right.
The research does caution that its findings are based primarily on data from Western populations, so generalizing to other cultures should be done carefully. Additionally, while the study relied mostly on cross-sectional data (comparing different age groups at a single point in time), some longitudinal data supports the patterns observed. The authors acknowledge that the weighting of different psychological capacities involves some subjectivity, and that individual trajectories can vary widely.
Yet, the central message is clear. The psychological capacities that matter most for navigating complex adult roles—intelligence, emotional regulation, moral reasoning, accumulated knowledge, and personality maturity—take decades to fully develop. For many, the age range from 40 to 65 represents the window of peak psychological fitness for complex, consequential decision-making. As Gignac and Zajenkowski conclude, "aging isn’t decline; it’s the long build-up to the most capable stage of adult life."
For a society that often treats aging as synonymous with obsolescence, these findings offer a much-needed reframing. The next time someone laments getting older, perhaps remind them: the best may be yet to come.
