The Pattern on the Stone

By W. Daniel Hillis

“Chapter 1: Nuts & Bolts”

The main theme of this chapter seemed to be about introducing the simplest bits of computer logic. Hillis likens the Boolean logic statement’s AND and OR to electrical wiring. This really helped me understand the principle behind the thinking. Last summer, I got into simple wiring in order to add some light and sound to some model prop replicas I was building as a hobby. After many hours of YouTube tutorials, I was able to understand how to wire LED lights in parallel so that if one light went out then the rest would stay lit. This would be like the OR statement. If you wire the lights in series, all of them need to work for the circuit to be complete.

I like the notion that a BIT is the “smallest difference that makes a difference” (10), since it can have only 2 states (in binary), on or off. This made me think of my 5th grade class when we learned about binary numbers and some basic computer stuff, although I didn’t really understand it all at the time.

“Chapter 2: Universal Building Blocks”

This chapter featured many diagrams that I found difficult to decipher. I don’t have the engineers background to read all the squiggles and lines properly, but I think I still got the gist of what Hillis is writing about. I see the use of logics blocks (AND, OR, and INVERT) as repeating parts of a puzzle that you can fit together to create different effects or outcomes. These Boolean logic functions use a set of rules to transform your input into an output. If you create a lookup table (LUT) with some memory, then you have a finite-state machine. I am familiar with LUTs since they are often used in color grading film or video footage. The state of the machine is written to the memory register millions of times a second; how often depends on the clockrate of the device. This very basic approach to describing how the computer works is extremely helpful for me. It is very difficult to design for or with a computer application if you don’t understand how it works, so I always try to learn as much as possible about its functions before starting with something new. I think the way Hillis breaks things down to their simplest parts helps me better understand how programming works.

“Chapter 3: Programming”

Way back in the early 1980s, I attempted to program a game on my Atari in BASIC. I had to store the game to memory on a cassette tape. I never really got more than a dot to move around. I think I didn’t fully understand the logic of how to put a program together in a way that I could get it to do what I want. After reading this chapter I feel like I have some ideas of how to improve the program I am working on for the class. The idea of extensible language and subroutines made me think about how I can approach my program as we move forward. I need to define new functions with subroutines. (The word “subroutine” is thrown around a lot on the various Star Trek shows, and now I have a much better understanding of what they were talking about.) In Processing, I need to figure out how to define an object as its own thing, so other objects can act independently or winter act with other objects. Then I can create some friends for Princess Florum and get them to dance at their digital disco.