Joseph Jacobs Thorndike (July 29, 1913 – November 22, 2005) was an American editor and writer. He was Managing Editor of Life for three years in the late 1940s, and a co-founder of American Heritage and Horizon magazines.
Thorndike was born and raised in Peabody, Massachusetts, a small town north of Boston. His father was a stockbroker, his mother a teacher. Thorndike was a straight A student at Peabody High, valedictorian of his class, and a writer for two school magazines.
At Harvard ('34) he majored in Economics, but spent much of his time at The Harvard Crimson, rising to Managing Editor his junior year, and to President his senior year.
In June 1934, he started work at Time magazine, writing people, miscellany and education articles. He was asked by Henry Luce to join a group planning a new picture magazine, and when Life debuted in 1936, Thorndike, though only 23, was an associate editor of the magazine.. His immediate boss at Life was John Shaw Billings, the first Managing Editor. Billings kept a diary in which, according to Loudon Wainwright's book The Great American Magazine: An Inside History of Life, he called Thorndike "a mulish young Yankee," and "a stubborn little New England cuss". Wainwright himself called Thorndike "a handsome, bright, reserved, efficient fellow...ambitious, proud, marked from the start for bigger things."
In 1946, as Life's circulation topped five million, Thorndike became the magazine's third Managing Editor, a position he held for three years. Toward the end of his stay, disagreements grew between him and Luce. Life, in late 1948, had published a "Life Goes To A Party" story about an uninhibited dance party in Hawaii, including photos of scantily-dressed partygoers. Luce's reaction was to subject the Managing Editor to more supervision, which Thorndike resisted. The dispute came to a head in August, 1949, after Luce circulated a memoir proposing an "Editor-in-Chief's Committee" that would decide on all future articles for the magazine. Thorndike read it, packed his briefcase and resigned.