The Great American Probability Machine

This program started my career in digital learning. I bought my first computer, an Apple II in February 1978 on their first anniversary. I talked my wife into letting me play with a computer for doing my checkbook and turning our houselights on and off. Though I was an educator who had worked with film technology, I never imagined that this machine would send my life rocketing in a new direction. That force hit the following summer at one of New England Apple Tree monthly club meetings where we came to see the wonderful new things people were dreaming up and take them home on cassette tapes. The buzz this meeting was about the latest West Coast phenomenon. Written by a guy we never heard of, Bruce Tognazzini, it was the first program to integrate text, animation (in Apple Lores graphics), and sound to tell an interactive story. It made use of the joysticks that came with the Apple II, and the first to tell a story. I fell in love. It made me see the personal computer as a tool I could use to express my vision of curriculum, and led me to start the first of my companies to express this vision.

I met Tog a few months later and we became good friends. He was by then working at Apple as an interface designer having a major impact on Apple and Mac screen designs. He continues to help companies improve user design today. Though Tog was not an educator, indeed, when he wrote the program he was the owner of a San Francisco Sony television store who bought his first Apple II about when I did as a toy to play with on his Sony Trinitron. The Probability Machine was the first program he wrote. Did this program turn him into a brilliant designer or was he already a great designer looking for a medium? I don’t know. But he was among the first to understand how to make screens both interactive, engaging, and wonderfully simple at the same time. For example, he introduced the graphic element through a story about the building of a great machine, a massive public works project in the late 19^th century, to build the understanding of probability. He tells us that the small rectangle on the bottom right of the machine is a door to let people access the machine. He took a common concept seen in many museums and made it a powerful tool that could go into the hands of students. I saw his vision as education’s vision.

As I designed educational software over the years since the Probability Machine appeared, I have often thought of Tog and his amazing 1500 lines of Woz’s Integer BASIC code, saved on and loaded from cassette tapes, and edited without a printer or any of the tools coders rely on today. I think of it now as I play with our spreadsheet version of Pascal’s Triangle that enables students to tell new stories and perhaps, just perhaps, be directed by this Spreadsheet Lab in a new life direction. There is great power in this tool when we let students use it to experiment and explore. Thank you Tog.

Art