In 1946, Douglas Engelbart was a young Navy radar technician in the Philippines when he read Vannevar Bush’s essay As We May Think in a Red Cross library. Bush imagined the Memex, a microfilm desk that linked documents by association, the way the mind works. Engelbart carried the idea into a world of punch cards and batch processing and concluded that computers should do more than calculate. They should augment human intellect, so people could manage problems growing faster than their brains could.

This episode traces that conviction from his Augmentation Research Center at the Stanford Research Institute to the stage in San Francisco on December 9, 1968. There, in 90 minutes, he showed the mouse, overlapping windows, linked documents, and live collaborative editing with video. It also follows what came after: an industry that applauded and went back to batch processing, a team that scattered to Xerox PARC, and a founder who watched his tools get sold without his purpose.

• Engelbart’s team practiced bootstrapping, using each tool they built to build a better one, much as a carpenter uses a crude hammer to make a finer hammer.
• The SDS 940 mainframe stayed in Menlo Park, about 30 miles away, linked to the stage by leased phone lines, custom 1200 baud modems, and microwave video beamed off a mountain.
• Bill English, who built the wooden mouse from Engelbart’s sketches, ran the video feeds backstage while Stewart Brand operated a camera at the lab.
• Former team members helped engineer the Xerox Alto by 1973, the machine whose interface Steve Jobs later saw on a tour of Xerox PARC.
• Engelbart felt a deep sense of loss as the interface spread and the philosophy was dropped, leaving him remembered mainly as the inventor of the mouse.