Cellular Automata: A Brief History
Considering that a computer is really a nesscity for investigating C.A's, it is surprising to find out that the idea is not actually that new. The idea for C.A's came before computers powerful enough to run them. But considering the idea sprang from the same fertile mind that developed the basic architecture no which almost all modern computers are based, is perhaps not so surprising.
John von Neumann was his name, and his contribution to the modern computer was so great that I can guarantee that the computer your using to read this on is based on his basic idea, the von Neumann architecture. Von Neumann was among other things a logician, and he saw computers not merely as number crunching machines but as engines of logic. He became convinced that life it's self was based on the same logical principles. The processes that created life had to be, in his view, a reconstructable series of events and interactions. In his mind there was no room for any mysticism or any kind of chance. "I shoulder at the thought that highly purposive organizational elements, like protein should originate in a random process"
He began to form some solid ideas from this general theory in the late 1940's. It's was in his lecture titled "The General and Logical Theory of Automata", that he first reviled his ideas to his fellow scientists. In this lecture he described a self contained, reproducing entity.
This first automata, was a little more than a theoretical construct. It consisted of a number of 'black boxes', which clawed along a long system of girders in a lake of the same materials that the entity was made of. The girders along which the entity moved also had information encoded on them. The information encoded on the girders (maybe in the form of rivets or cross beams), where detailed instructions for building a copy of it's self. Each one of the three 'black boxes' each had a specific job to do.

The Factory. This boxes job was to take materials from the lake around it and, under instructions from The Duplicator and build them in to new 'black boxes'.
The Duplicator. This box took the instructions on the girders and copied them. One copy it kept, the other it passed to The Factory.
The Controller. This box was the computer which controlled the entity.

Because the duplicator held a copy of the instructions it could, when the new entity was finished, pass them on to it. This act made the new entity fertile, it could now reproduce it self. Thus the world was introduced to it's first self reproducing machine.
This was fine as a theory, but it relied on these 'black boxes' too much. There was no real detail of what was going on inside of them.
It was a friend and fellow mathematician, of Neumann's, Stanislaw Ulam that came up with the answer. Instead of the entity swimming thought a lake, the entity lived in a universe like a chessboard, an endless grid of cells. Each of these cells had a state which was determined by a set of rules, for each tick of the clock which governed this universe each cell would consult these rules to see what it's state would be on the next tick. Thus the Cellular Automata was born, although it was not called that until Arthur Burks came to edit von Neumanns papers on the subject, Ulam called these entities tessellation structures.
Armed with this idea von Neumann 'rebuilt' his entity. This time it was a huge collection of cells, 200,000 of them. Each cell could be in any one of 29 different states. This made it the most complex cellular automata ever, far more complex than could be simulated manually or on the computers of the time.
All the components of the original design, where there. The factory, duplicator and controller making up the head of the entity (50,000 cells) and the 'tape' which held the instructions formed a long tail (150,000 cells). From the head came a small constructing arm which connected the child to it's parent, an umbilical cord. The complexity of this automata was considerable and even von Neumann underestimated this. He never did finish a written proof of the automata's viability, despite a years work on it.
For years after von Neumanns death, cellular automata remained a fringe subject for both scientists and mathematicians. But interest was rekindled in the early 1970's by a mathematician by the name of John Conway. He developed a very simple cellular automata, which he called, the game of life. The game of life or more simply life, was had very simple rules, they had to be because at first the automata was an entirely manual thing. The universe that the game of life was played out in started out as a Go board. Squared paper was added to the board to extend the frontiers of this world.
As stated the rules are very simple. Each square can be in two states, either alive or dead. A dead square will become alive in the next generation if three of it's neighbors are alive and a live square will die unless it has 3,4 or 5 live neighbor. That's it.
And yet from these simple rules complex behaviors emerged. Patterns 'crawled' or glided across the board, patterns exploded in brief periods on intense activity and left behind 'blinking' debris. It seemed a whole universe of deferent life forms could be created on this go board.
The board it's self was to small and any pattern of complexity quickly grew to large to be shown on the board, and adding paper to the sides of the board was not an idea way of expanding the universe. However this idea was very much in the right place at the right time. Computers where interactive computers, with displays where becoming common place in unoversities across the world. Life was idealy situted to studied by these new tools. The grid on which life existed could be mapped directly to areas of memory.