Computers—the machines we think with

by D. S. Halacy

Thus far we have talked of the computer only as a tool to be studied and not as an aid to learning in itself. In just a few years, however, the “teaching machine” has become familiar in the press and controversial from a number of standpoints, including those of being a “dehumanizer” of the process of teaching and a threat to the apple business!

Actually, the computer has functioned for some time outside the classroom as a teaching machine. Early applications of analog computers as flight simulators were true “teaching machines” although perhaps the act was not as obvious as classroom use of a computer to teach the three R’s. Even today, there are those who insist that such use of the computer by the military or industry offers more potential than an academic teaching machine. Assembly workers have been taught by programmed audiovisual machines such as Hughes Aircraft’s Videosonic trainer, and the government has taught many technicians by computer techniques. A shrewd observer, however, noting that the computer is called stupid, bluntly points out that any untaught student is in the same category, and that perhaps it takes one to teach one.

A strong motivation for looking to the machine as a public teaching tool is the desperation occasioned by the growing shortage of teachers. If the teaching machine could take over even some of the more simple chores of the classroom, early advocates said, it would be worth the effort.

Formal study of machine methods of teaching have a history of forty years or more. In the 20’s, Sydney Pressey designed and built automatic teaching—or more precisely, testing—machines at Ohio State University. These were simply multiple-choice questions so mechanized as to be answered by the push of a button rather than with a pencil mark. A right answer advanced the machine to the next question, while an error required the student to try again. Pressey wisely realized the value in his machines; the student could proceed at his own pace, and his learning was also stimulated by immediate recognition of achievement. To further enforce this learning, some of the teaching machines dispensed candy for a correct answer. Using this criterion, it would seem that brighter students could be recognized by their weight.

Unfortunately, Pressey’s teaching machines did not make a very big splash in the academic world, because of a combination of factors. The machines themselves had limitations in that they did not present material to be learned but were more of the nature of a posteriori testing devices. Too, educators were loath to adopt the mechanized teachers for a variety of reasons, including skepticism, inertia, economics, and others. However, machine scoring of multiple-choice tests marked with special current-conducting pencils became commonplace.

Another researcher, B. F. Skinner, commenced work on a different kind of teaching machine thirty years ago at Harvard. Basically his method consists of giving the subject small bits—not computer “bits,” but the coincidence is interesting—of learning at a time, and reinforcing these bits strongly and immediately. Skinner insists that actual “recall” of information is more important than multiple-choice “recognition,” and he asks for an answer rather than a choice. Called “operant reinforcement,” the technique has been used not only on man, but on apes, monkeys, rats, dogs, and surprisingly, pigeons.

During World War II, Dr. Skinner conducted “Project Pigeon” for the military. In this unusual training program, the feathered students were taught to peck at certain targets in return for which they received food as a reward. This combination of apt pupils and advanced teaching methods produced pigeons who could play ping-pong. This was in the early days of missile guidance, and the pigeons next went into training as a homing system for these new weapons! To make guidance more reliable, not one but three pigeons were to be carried in the nose of the device. Lenses in the missile projected an image before each pigeon, who dutifully pecked at his “target.” If the target was in the center of the cross hairs, the missile would continue on its course; if off to one side, the pecking would actuate corrective maneuvers. As Project “Orcon,” for Organic Control, this work was carried on for some time after the end of the war. Fortunately for the birds, however, more sophisticated, inorganic guidance systems were developed.

The implications of the pigeon studies in time led to a new teaching method for human beings. Shortly after Skinner released a paper on his work in operant reinforcement with the pigeons, many workers in the teaching field began to move in this direction. For several years Skinner and James Holland have been using machines of this type to teach some sections of a course in human behavior to students at Radcliffe and Harvard. Rheem Califone manufactures the DIDAK machine to Skinner’s specifications.

To the reasons advanced by those who see teacher shortages looming, Skinner adds the argument that a machine can often teach better. Too much time, he feels, has been spent on details that are not basic to the problem. Better salaries for teachers, more teachers, and more schools do not in themselves improve the actual teaching. Operant reinforcement, Skinner contends, does get at the root of the problem and, in addition to relieving the teacher of a heavy burden, the teaching machine achieves better results in some phases of teaching. It also solves another problem that plagues the educator today. It is well known that not all of us can learn at the same rate. Since it is economically and culturally impossible except in rare cases to teach children in groups of equal ability, a compromise speed must be established. This is fine for the “average” child, of whom there may actually be none in the classroom; it penalizes the fast student, and the slow student perhaps even more. The teaching machine, its proponents feel, takes care of this difficulty and lets each proceed at his own rate. Since speed in itself is no sure indicator of intelligence, the slow child, left to learn as he can, may reach heights not before dreamed possible for him.

Many educators agree that automated teaching is past due. James D. Finn, Professor of Education at the University of Southern California, deplores the lack of modern technology in teaching. “Technology during the period from 1900 to 1950 only washed lightly on the shores of instruction,” he says. “The cake of custom proved to be too tough and the mass production state, at least 100 years behind industry, was not entered except here and there on little isolated islands.”