The 'Big 4' of '70s Sitcoms Changed TV Forever. Here's Why

The article argues that the “Big 4” of 1970s sitcoms changed television permanently by building on the era’s shift from early-70s rural programming to issue-driven comedy. It recalls how CBS’s “rural purge” removed successful country-leaning shows to pursue a more modern, urban audience, opening space for Norman Lear-style sitcoms like All in the Family. It then lays out selection criteria: debut in the 1970s, big ratings, major format or rule-breaking impact, and long-term cultural reach. The piece also applies a “one show per family tree” rule to avoid overlapping Lear-created universes. The countdown begins with All in the Family (1971–79).