Across social media in 2026, adults are cataloging the quiet, sometimes startling moments when they found themselves explaining foundational knowledge to peers who had simply never encountered it. These stories, accumulating in comment threads and viral posts, are less about mockery than about a deeper reckoning: that what we call common knowledge is not common at all, but the product of particular circumstances, educations, and exposures. The trend holds up a mirror to a society where information is everywhere yet understanding remains unevenly distributed, raising quiet questions about how w