The Builders.
Alan Kayb. 1940
Invented the Dynabook concept, led the development of Smalltalk, and formulated the object-oriented programming paradigm at Xerox PARC.
The computer as medium, not tool
Alan Kay's central and recurring idea is that the computer is the first metamedium, a medium that can simulate any other medium, and invent new ones. Most people never see this. They use computers as faster typewriters or more efficient filing systems. Kay kept asking what no previous medium could do.
Smalltalk and the object
At Xerox PARC in the early 1970s, Kay and his Learning Research Group built Smalltalk, a language in which everything is an object and everything happens by sending messages. The design was partly an implementation philosophy and partly an educational one. Kay wanted children to be able to program their own media.
The object metaphor has been distorted beyond recognition in most modern languages, but the original form had a biological intuition: a system of many autonomous agents, each processing messages in its own way, with no global state.
The Dynabook
Kay's most influential unbuilt thing is the Dynabook, a portable computer for children, sketched in 1968, designed to be a personal dynamic medium. It never shipped. But the laptop is its shadow, the iPad is a partial shadow, and the idea of personal computing as literacy is Kay's idea.
"The best way to predict the future is to invent it."
He has spent fifty years trying to.
λx.x — everything is an object, everything is a message
Claude E. Shannon1916-2001
Founded information theory. Invented the bit. Proved that reliable communication over a noisy channel is always achievable up to a finite rate.
The one-man revolution
Shannon's 1948 paper did not improve communication theory, it created it. Before him there was folklore and practice. After him there was a physics.
His central move was separating meaning from information. A message carries information in proportion to how much uncertainty it resolves, with no reference to what the message says. This freed the engineering problem entirely from the semantic one and made both tractable.
The playful mind
Shannon was known at Bell Labs for riding a unicycle down the corridors, sometimes while juggling. He built mechanical mice that learned mazes, a chess-playing machine, and a device called the "Ultimate Machine" whose only function was to switch itself off.
This playfulness and the rigour were not in tension. He moved between abstract proofs and physical toys with the same facility, the same curiosity about what systems could do and why.
What he gave every digital system
Shannon gave us the bit, the channel capacity, and the entropy of a source. Every compression algorithm, every error-correcting code, every modern cipher descends from these three ideas. The architecture of the internet is drawn in the margins of his 1948 paper.
"The fundamental problem of communication is that of reproducing at one point either exactly or approximately a message selected at another point."
He solved it. The solution is everywhere you look.
H = −Σ p(x) log₂ p(x) — entropy, the average surprise
Vannevar Bush1890-1974
Conceived the memex, a desk that links and trails through knowledge. The intellectual ancestor of hypertext and the web.
The man who organized American science
During the Second World War, Bush ran the US Office of Scientific Research and Development, coordinating radar, the proximity fuse, and (with Oppenheimer and others) the Manhattan Project. He had more influence over the direction of science in that period than any other single person.
When the war ended, he wrote "As We May Think", not a report on weapons but a vision of what scientists should build next. The answer he gave was a machine for the mind.
The memex
The memex was a hypothetical desk that held a person's entire library on microfilm, could retrieve any document instantly, and let the user build trails of association between documents. A trail was a named, saved path through the knowledge base that could be handed to another person.
Bush's intuition was that human thought moves by association, not by alphabetical index. A good memory machine should move the same way.
The legacy
Bush never built the memex. But Douglas Engelbart read "As We May Think" in a Red Cross library in the Philippines in 1945 and decided that was what he would do with his life. Ted Nelson coined "hypertext" working from Bush's idea. Tim Berners-Lee cited it when explaining the web.
The memex is the most influential piece of hardware that was never built.
memex → trail → web — association, made mechanical