Just a Gwai Lo fun within prescribed limits [?]

Rudy Rucker's third chapter of The Lifebox, The Seashell, And the Soul tackles evolution as computation and the possibility or artificial life (which he shortens to a-life). Of the three so far, this is the most accessible, talking about activators and inhibitors (relating them to ideas and their spread), and later in the chapter, cellular automata algorithms used to produce what look like trees. Most compelling, however, was his discussion on search method algorithms, though as a computer geek, I had to remind myself that he did not limit himself to search engines as we know them on the Internet but the ways and the feasibility of the ways we as humans and potential artificial life system would search for the solution to a problem. He distinguished between best solutions and acceptably good solutions, because it's far more efficient, not to say worthwhile, to find the acceptably good solutions over best solutions, because the later most often means you have to search through all possible solutions:

The fact is, given a large enough search problem, none of our various search methods is likely to find the absolute best solution with a feasible amount of time. But so what? After all, absolute optimality isn't really so critical. In any realistic situation we're quite happy to find a solution that works reasonably well. Nature is filled with things that work in clever ways, but it's a delusion to imagine that every aspect of the biome is absolutely optimal. Surely we humans don't have the absolute best bodies imaginable, but—hey—our flesh and bone holds up well enough for eighty or so years. We do better than our rival apes and our predators, and that's enough.

Nearer to the end he quotes at length from his novel The Hacker and the Ants, about a scenario in which software developers create virtual worlds in which their simulated robots compete amongst themselves in virtual environments. I imagined several homes in The Sims, with robots instead of humans, evolving in houses each slightly different but covering all the possibilities of combinations within those homes, the robots having descended into complete anarchy. I haven't read any of Rucker's novels but they can be found at the local used bookstore, so it's about time I got my hands on a few, since if he uses scenes from them to prove a point, he must think that they have stood the test of time reasonably well.

In the first chapter of The Lifebox, the Seashell, and the Soul: What Gnarly Computation Taught Me About Ultimate Reality, the Meaning of Life, and How to Be Happy, Rudy Rucker, science fiction writer and computer scientist sets out his argument, which, handily, is the title of the chapter, "Computation Everywhere". The chapter is part organizing—in which he lays out the structure of the rest of the book—and part introductory, defining computations as “a process that obeys finitely describable rules” and classifies them at least two ways, on feasibility and unpredictable lines, as well as how the computations go about. Along the first, computaions can be:

• feasible and predictable
• fessible and unpredictable
• unfeasible and predictable
• unfeasible and unpredictable

and the second, they can be classified “four main behaviors for arbitrary computations that are left running for a period of time”:

1. enter a constant state
2. generate a repetitive or nested pattern
3. produce messy, random-looking crud
4. produce gnarly, interacting, nonrepeating patterns

He then goes on to define terms such as the Principle of Computational Equivalence, the Principle of Computational Unpredictability and universal computations, moving on to analytical machines. The word "machine" in Turing Machine tricked my non-theoretical non-computer science into thinking it was necessarily a physical thing rather than a mathematical or algorithmic concept. Emulation—and that any computer can, theoretically, emulate another—is a concept I have a fairly easy time grasping, if not so much later concepts such as cellular automaton (this time the word cellular tricking my brain into thinking about biological—i.e. existing in physical form—cells), and I'd probably have to see the cellular automaton rules play out in an animation, if maybe sped up.

In subsequent chapters Rucker applies computations to biology and physics, the latter I did well enough in high school to be able to follow along and the former I have about zero knowledge of. The book is so far well-written enough that I can plod through and jump back or pause to research more detailed explanations, though, so plod on I will.