Source: In June 1954 a column titled “Inside TV” by Eve Starr was published in a North Carolina newspaper, and Starr reported on two jokes told by Groucho Marx during his show. Boldface has been added:

Groucho quips: “It takes a heap of spending to make a house a home.” His best advice to contestants is: “If you speak when angry, you’ll make the best speech you’ll ever regret.”

Misattribution: Often misattributed to Laurence. J. Peter, Ambrose Bierce and others but no authentic source is yet found.