Tag Archives: physical system

The Eight Queens

One solution to the puzzle.

I’ve written a lot lately about the physical versus the virtual. I’ve also written about algorithms and the role they play. In this post, I revisit both by exploring what is, for me, an old friend: The Eight Queens Puzzle. The goal is to place eight chess queens on a chessboard such that none can take another in a single move.

The puzzle is simple enough, yet just challenging enough, that it’s a good problem for first-year student programmers to solve. That’s where I met it, and it’s been a kind of “Hello, World!” algorithm for me ever since.

I thought it might be a fun way to explore a simple virtual reality.

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Determined Causality

The ideas of free will, causality, and determinism, often factor into discussions about religion, morality, society, consciousness, or life in general. The first and last of these ideas seem at odds; if the world is strictly determined, there can be no free will.

But we are confronted with the appearance of free will — choices we make appear to affect the future. Even choosing not to make choices seems to affect our future. If reality is just a ride on fixed rails, then all that choosing must be a trick our brains play.

These questions are central to lives, but answers have remained elusive, in part from differing views of what the key ideas even mean.

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Information Systems

Last time I explored five physical systems. This time I want to implement those five systems as information systems, by which I mean numeric versions of those five systems. The requirement is that everything has to be done with numbers and simple manipulations of numbers.

Of course, to be useful, some parts of the system need to interact with the physical world, so, in terms of their primary information, these systems convert physical inputs into numbers and convert numbers into physical outputs.

Our goal is for the numeric systems to fully replace the physical systems.

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Causal Systems

Recently, I’ve been involved in some discussions about causality, and some of those discussions have struggled to find any resolution, which I find frustrating. I don’t think people need to agree on ideas, but my experience is that usually people can agree on how to frame and talk about those ideas.

I sometimes get the feeling people are so set on disagreeing that they don’t always engage on what the other party is saying. I never know if it’s a lack of comprehension, a lack of willingness, or (on my part) a lack of communication skill or sufficient explanation.

So here are some things I think (I hope) are uncontroversial.

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