But we got more interested in answering questions that were typed into the computer. So I had three or four students who were writing programs to understand, to some extent, ordinary English printed text or typed... typed text; so there’s no pattern recognition problem, you just... the computer knows exactly what letter... what key has been pressed and so it’s not a matter of recognizing a visual form.

So there was one student named Daniel Bobrow who wrote a program that was fairly successful in solving first year high school algebra problems. So you could type a problem like this: the… a certain automobile can go... can get 15 miles per gallon; the distance from Boston to New York is 230 miles or whatever. How many gallons will it take to go... drive from New York to Boston or whatever. And Bobrow’s program was able to answer enough to score it a 9th or a 10th grade level for answering such questions. And it did it remarkably well considering that it didn’t know what most of the words meant. It knew that plus meant to add and so it knew a lot of ordinary words that had mathematical meanings and the program was designed that every sentence would be an equation – X=Y+Z – and it didn’t know what a car was or what gasoline was or even miles, but it knew what per means. Miles per gallon is a fraction. And this was a dramatically successful program because it, in fact, was comparable to typical not very good students in high school for that kind of problem.