Making sense of it all in an 'information revolution'

Making sense of it all

The American Philosophical Association selected IUB's Jon Barwise and his Stanford University colleague as Educom winners in the area of philosophy for their collaborative development of the educational computer programs "Turing's World," "Tarski's World" and "Hyperproof," which introduce students to the principles of logic.

in an 'information revolution'

'Turing's World' (and Barwise's)

By Hal Kibbey

In the age of visualization, what chance does formal logic have to compete for the attention of students? Is logic even relevant to modern life, which seems to be swept along by forces such as the mindless computer and the "information revolution?"

"Logic is not playing games with symbols. Logic is the science of valid reasoning," said Jon Barwise, College Professor of philosophy, mathematics and computer science at Indiana University's Bloomington campus. Valid reasoning is important to everything from business and medicine to law and ethics.

However, introductory logic courses have traditionally treated the subject in an abstract way, with rules to be memorized and then applied to proving that a particular statement follows from some other statements. The important relationship between statements and the world they describe is seldom included. How can a teacher get across the principles of logic without losing all relationship to the world around us?

Barwise and his collaborator, John Etchemendy, professor of philosophy at Stanford University, came up with a solution to this and related problems -- three computer programs to help students learn logic. The programs have won for the two professors the 1997 Educom Medal in the category of philosophy.

Educom is a non-profit consortium of colleges, universities and other organizations dedicated to the transformation of higher education through the application of information technologies. It has 600 institutional members and nearly 100 corporate associates. The award is considered Educom's highest recognition of excellence and accomplishment on the part of individuals who are dedicated to improving the undergraduate learning experience through information technology.

Winners of the Educom award receive a silver medal, a bronze statue and a check for $2,500. Barwise and Etchemendy were honored at a special presentation at the association's annual meeting Oct. 28-31 in Minneapolis, Minn.

"The creation of educational courseware is very important if higher education is to take advantage of the information revolution. But this kind of creative work is not much encouraged, since it does not fit into any of the traditional research/teaching/service categories. I would hope that this award will make faculty think about the importance of this kind of activity and encourage some of them to get involved," Barwise said.

Each year, Educom works with professional societies to identify individuals who have demonstrated that the integration and dissemination of information technology can help improve undergraduate teaching. This year, Educom worked with the American Philosophical Association, the American Political Science Association, the Geological Society of America and the American Society of Mechanical Engineers.

The American Philosophical Association selected Barwise and Etchemendy as winners in the area of philosophy for their collaborative development of the educational computer programs "Turing's World," "Tarski's World" and "Hyperproof," which introduce students to the principles of logic.

Each package comes with a textbook and is designed for students to use outside of class. Barwise sees the courseware as "an intellectual erector set where students can explore the topics and work problems. The computer helps them do it efficiently and allows them to do things that you just can't do with a pencil and paper."

The first of these software packages was "Turing's World," developed in 1986 to teach basic concepts of logic and computation. "Turing's World" permits students to build and run complex Turing machines easily, which would be almost impossible using paper and pencil. The Turing machine, developed by the English logician Alan Turing in 1936, became the fundamental model for the computer. It remains one of the basic principles of computer science and beginning computer science courses.

But it is difficult to demonstrate a powerful Turing machine on a blackboard, because most Turing machines require hundreds of steps to do a complex task. It is impractical to construct such a Turing machine during class or as a homework problem, so Barwise and Etchemendy decided to use the computer to teach about the computer. With "Turing's World," a student can design a Turing machine, check to see whether it works, and find and correct any mistakes. The many tasks that would take hours with pencil and paper are done in moments by the computer.

"Before 'Turing's World,'" Barwise said, "it was hard for beginning students to really grasp the power of the models because all they could do was create little toy Turing machines on paper. Our idea was to provide a graphic environment in which students could really program Turing machines, watch them at work and debug them.

"There was simply no comparison in the quality of understanding between students who used 'Turing's World' and those who did not have it available. 'Turing's World' let students go much farther much faster and have more fun at the same time."

Using the computer to teach the principles of computer science was so successful that Barwise and Etchemendy developed "Tarski's World," which teaches the language of elementary logic. Logic is about the relationships between sentences and the world, so Barwise and Etchemendy depicted "worlds" in the form of diagrams. "Tarski's World" presents a variety of worlds in the form of pictures of blocks on a grid. Logical sentences refer to a diagram of a world, and students can see for themselves whether statements such as "The small cube is behind the large tetrahedron" are true or not.

Because the material is presented on a computer, the students can manipulate the worlds, change the worlds and construct their own worlds. They get far more practice than would be possible with conventional methods, because the computer does the tedious but simple parts quickly, checks the student's work and shows the student any errors.

"Hyperproof," the third software package developed by Barwise and Etchemendy, goes beyond the language of logic to teach the principles of valid reasoning.