David's Blague

Ze Frank has this episode of The Show where he talks about "brain crack." It's the stuff your brain gets addicted to because it could be good. Watch the episode:

http://www.zefrank.com/theshow/archives/2006/07/071106.html

This, Internet, is my brain crack. Been thinking about this for a long time, hoping to write something long. Well, here's something short, instead.

Claude Shannon Invented Computers
Claude Shannon invented computers. Not all at once, and not all by himself, but when you think about the guy who had the "Aha!" moment, it's him. In 1937 (there were, it seems, a whole lot of "Aha!" moments in the thirties), he published his Masters thesis, which showed how Boolean logic and electrical circuitry are the same. One can (and Shannon did) translate back and forth between electrical circuitry and Boolean logic.

To me, that's the "Aha!" moment. He's the guy who made it all possible. In his paper, he designed several electronic circuits, wrote them up in Boolean operations, and became the first guy who "programmed" electronics by manipulating logic. And before the comments start flowing, yeah, I can think of quite a few precursors. Heck, Euclid did the same for manipulating physical space, right? But Shannon's most immediate precursor was George Boole, whose logic system he wrote about.

George Boole Invented Binary Logic
George Boole reduced logic down to True and False. Every statement in his system could always be reduced down to True (a statement that follows from the accepted axioms) and False (one that doesn't). If you took a philosophy class in college and had to make truth tables, it's really Boole's fault.

Boole wasn't the first to take an interest in binary systems: that's an old, old idea. Pingala used a kind of binary notation for describing poetry. Eye of Horus is a binomial system, base two just like binary. Knuth even points out in The Art of Computer Programming that English wine merchants have used a binary system for buying and selling wine for hundreds of years. But George Boole was the one who invented binary logic, and that was one of the necessary pieces for Shannon's thesis.

Leibniz Invented Binary Arithmetic
A century or so before Boole, Leibniz got fascinated with how the I Ching seemed to be organized by a binary mathematical notion: if you make a broken line a zero and a solid line a one, they can be placed in sequential binary order. Gottfried Wilhem von Leibniz went further than that, though. In his Explication de l'Arithmetique Binaire, Leibniz showed how decimal numbers have a one-to-one correspondence with binary. He went on to advocate use of binary, not for the ability to do anything particularly new, but for what it shows about numbers.

Anyone who's reading this should know, I've read Glaser's History of Binary and Other Nondecimal Numeration, so I know he's got a whole chapter called "Before Leibniz." Well, none of it convinced me that I've gotten the wrong guy. Leibniz had probably read Lobkowitz, and probably some of the others who had published, but Leibniz "got" that binary is important, and foundational, and not just another kind of enumeration- it's the one using the least number of digits.

Francis Bacon Invented Binary Encoding
I'm going out on a limb here. Francis Bacon was probably not the first guy, but he did devise an encoding system for English text that only used two characters. He used it as a cipher, but it's not all that different from ASCII that we use now, and for that reason alone he deserves mention here.

Bibbity Bobbity Boo
Put it together, and what have you got? A way to use electricity to do math, encode text, and perform logic operations. Church, Turing, Kleene, and even Gödel all came with complicated logical models for manipulating symbols, but Shannon came up with a simple one, and showed us how to use it with electrical circuits we already had.

Sure, Zuse, Von Neumann, Mauchly, Eckert, they all built machines. But people had been building machines for a long time. Heck, Leibniz had one that could add, subtract, multiply, divide. Ada Lovelace and Charles Babbage had one. Jacquard programmed his fricken looms. But Claude Shannon showed us, hey, just use electricity.

So, if you're here, and you're trying to answer the question, "who invented computers?" my answer is, we're all still doing it. But Claude Shannon, the guy who had that "Aha!" moment in 1937, gets my vote for Parent-of-Digital-Computing.

Labels: computers, software