Cumulative Record. Chapter 13: Teaching Machines. Quote 15

A simple technique used in programming material . . . is exemplified in teaching a student to recite a poem. The first line is presented with several unimportant letters omitted. The student must read the line “meaningfully” and supply the missing letters . . . Subsequent frames are increasingly incomplete, and eventually —say, after 20 or 24 frames—the student reproduces all four lines without external help, and quite possibly without having made a wrong response. (p. 200)