A brilliant polymath with a Ph.D. in chemical engineering—he was Dr. Grove when he wasn’t simply Andy—the longtime Intel CEO (INTC) and then chairman taught the nerds about the importance of marketing. The public craved “Intel Inside” for reasons it never could have articulated beyond Intel’s ubiquitous and convincing advertising. Grove helped popularize cubicle culture: If someone as mighty as the immigrant-turned-technology-titan didn’t rate an office, neither did you. He was the rare technologist who thrived as a business leader, a master strategist, and a popular explainer of his hard-won wisdom. Only the Paranoid Survive educated a generation of business leaders in the language of market analysis—the “strategic inflection point”—and in how to navigate the proper course through a crisis.

Grove, who died at his home in Los Altos, Calif., on March 21 at 79, was more than a business leader. He wrote gracefully—in Fortune—about his battle with prostate cancer. He mentored Intel’s leaders as well as entrepreneurs outside Intel’s walls, including Steve Jobs.

The epitome of an American success story, Grove was profane, direct, argumentative, and full of mirth—often in one breath. His death is a reminder of a time when Silicon Valley’s disruptive products were tangible, life changing, and technically brilliant—if sometimes flawed. That description isn’t a bad epitaph for Grove himself. Intel was famous for a “copy exactly” manufacturing process. Its great leader was one of a kind.

A version of this article appears in the April 1, 2016 issue of Fortune.