They ran an SDS-940, one of the early timesharing computers that allowed many people to use the same machine at once.
Compared with punch cards, it felt like stepping into the future. You could type something and the computer answered immediately.
For someone who liked exploring from the inside out, it was hacker heaven.
The machine ran a collection of experimental languages. One of these was specialized in processing text. With some coding, you could look for a phrase and substitute another. If someone typed “I feel unhappy,” the program might reply “Why do you feel unhappy?”
The machine wasn’t understanding anything. It was spotting patterns and rearranging them. At the time it felt like a clever trick with language. Only later did it become clear that the same basic idea—recognizing patterns instead of understanding meaning—would begin turning up in many other places.
But the illusion could still be convincing. If someone typed “I hate my history teacher,” the program might respond, “Tell me more about your teacher.” People sometimes reacted as if the machine were actually listening.
At the time it felt like a toy.
My attention kept drifting somewhere else: the operating system.
One Sunday afternoon at Dial-Data I had the SDS-940 all to myself and started doing what young hackers do when nobody is watching—poking around inside the system to see how it worked.
One thing caught my eye.
The system spent an enormous amount of time shuffling information between memory and disk. Watching it run, it felt wasteful.
So I tried a small experiment.
I spent the evening tweaking code in the operating system so it saved only memory that had actually changed. Around three o’clock Monday morning, the test came together, and the system suddenly felt different. The frantic shuffling had almost disappeared. Programs ran noticeably faster.
The whole machine felt lighter on its feet.
Satisfied with my experiment but totally exhausted, I went home for some sleep. What I didn’t do was put the operating system back the way I had found it.
The next morning at 8 a.m., the incessant ringing of the phone woke me.
“Southworth, were you here yesterday?”
I said yes.