Nobel laureate James Heckman explains why ages zero to five are critical for brain development and lifelong outcomes. He discusses the Perry Preschool Program's surprising health benefits 35 years later, why low-cost home-visiting programs that engage parents outperform expensive institutional interventions, and how "dynamic complementarity" means early skills beget later skills. Heckman also critiques economics' "credibility revolution," arguing the field has traded big-picture understanding for narrow "clean" answers—illustrated by his recent Wall Street Journal op-ed showing that contrary to popular belief, the China trade shock created net job gains for the US.