What makes this observation sting is that Einstein—a man who spent his life mapping the universe's deepest secrets—chooses to express doubt about the cosmos rather than about human nature. The joke works precisely because we expect the reverse: surely an astrophysicist would marvel at infinity while dismissing human folly as ordinary. Instead, he suggests that stupidity possesses a kind of creative, boundless quality that rivals the physical world's mysteries. Consider how a single person can reinvent the same destructive mistake across decades of their life, or how societies repeat historical blunders despite warning signs: there's something almost cosmic in stupidity's ability to escape prediction or calculation, which is exactly what makes it worthy of Einstein's wry comparison.