Stop Thinking You Know How Things Have Changed…Go Measure it

Claims that “kids these days” are in decline persist across eras. These complaints, however, rest largely on biased intuitions rather than rigorous evidence. It is not the case that everyone else before was wrong about decline but this time we are finally right. We highlight how intuitions of the generational decline are due to researchers being odd. Judgments are further distorted by misperceptions of the present, idealized memories of the past, presentism, all producing comparisons between reality and fiction. Historical examples and contemporary data illustrate how technologies and practices unfamiliar to older cohorts are over-indexed as the villain and often misassigned. We argue that credible claims about secular changes require (a) broad time horizons that avoid arbitrary cutoffs; (b) preregistration to curb confirmation bias; and (c) strict tests of measurement invariance, broadly construed to include shifting diagnostics, reference groups, reporting norms. Re-analyses that honor invariance overturn canonical narratives (e.g., “reverse Flynn effects,” a “narcissism epidemic”). While people and societies do change, many trends are cyclical rather than monotonic. We conclude with a practical framework: before inferring decline, ask whether the change is measured, whether the past benchmark is accurate, whether the metric is comparable across time.