Silicon Valley is more a state of mind than a place. It is not a single valley — the hills around Palo Alto, Cupertino and Mountain View in northern California are not high enough to form one. Nor is its chief business now silicon, the base layer of semiconductors since the rise of companies such as Fairchild Semiconductor, Motorola, Texas Instruments and Intel.

Silicon Valley’s relentless reinvention is evident in the fact that two of its best-known companies are Google (now Alphabet) and Facebook. Neither is in silicon. Google was founded only in 1998 and Facebook is even younger. It was created on the other side of the country, in a Harvard dormitory, by Mark Zuckerberg and friends in 2004.

One seminal moment in Silicon Valley history occurred in 1985, as Intel lingered in what Andy Grove — the first employee of its founders, Robert Noyce and Gordon Moore — used to call “the valley of death”. Grove, who later became Intel’s chief executive and chairman, and who died this week aged 79, meant a period when a company has been outsmarted.