Monday, 27 April 2020

book review: Generative Art

Matt Pearson.
Generative Art.
Manning. 2011

This is an introduction to producing generative art using the Processing language. I had a brief fiddle around with Processing a while ago, and produced a little app for playing around with the superformula; I read this book to see how Processing is used for art. Processing was invented to be an “easy” language for artists to learn. In its original form, it is based on a stripped down version of Java. I discovered with a bit of Googling that there is also a Python Mode available, which I find preferable.

The book has an introduction to generative art, and introduction to Processing (Java Mode), and three example sections on its use for art: emergent swarming behaviour, cellular automata, and fractals. There are lots of good examples to copy and modify, and also lots of pictures of somewhat more sophisticated examples of generative art.

There is a lot of emphasis on adding noise and randomness to break away from perfection: [p51] There is a certain joylessness in perfect accuracy. Now, fractals are one area that can provide exquisite detail, but are they too accurate? I decided to take his advice, and add some randomness to the well-known Mandelbrot set: instead of a regular grid, I samples the space at random, and plotted a random-sized dot of the appropriate colour:
It certainly has a different feel from the classic Mandelbrot set picture, but I’m not going to claim it as art. However, the Python Mode Processing code is certainly brief:
def setup():
    size(1200, 800)
    noStroke()
    background(250)
    
def draw():
    cre,cim = random(-2.4,1.3),random(-1.6,1.6)
    x,y = 0,0
    n = 0
    while x*x + y*y < 4 and n < 8 :
        n += 1
        x,y = x*x - y*y + cre, 2*x*y + cim
        
    fill((n+2)*41 %256, (256-n*101) % 256, n*71 %256)
    r = random(2,15)
    circle(cre*height/4+width/2,cim*height/4+height/2,r)

Note for publishers: don’t typeset your books in a minuscule typeface, grey text on white, with paper so thin that the text shows through, if you want anyone over the age of 25 to read it comfortably. I frankly skimmed in places. Nevertheless, this book should provide a good introduction to Processing for artists, providing basic skill that can then be incrementally upgraded as time goes by.



Thursday, 23 April 2020

book review: Unthinkable

Helen Thomson.
Unthinkable: an extraordinary journey through the world’s strangest brains.
John Murray. 2018

The brain is amazing, and amazingly complex. One way to learn about how it works is to study it when it goes wrong, or behaves differently from normal. Here Thomson, following in the footsteps of Oliver Sacks, provides multiple different windows onto different brains. Each of the nine main chapters is based on a single person with a particular difference, with a personal conversation, discussion of other similar cases, and some suggestions of what is going on, or not going on, in these different brains.

We get a man with a perfect autobiographical memory, a woman who can’t find her way around (Developmental topographical disorientation), a colour-blind man who sees people with colourful auras (synaesthesia), a man whose personality changed after an electric shock and is now compelled to paint all day (sudden artistic output syndrome), a deaf woman who constantly hallucinates music (Musical ear syndrome, an aural version of Charles Bonnet syndrome), a schizophrenic man who thinks he is a tiger (clinical lycanthropy), a woman completely detached from her feelings (depersonalisation disorder), a man who thought he was dead (Cotard’s syndrome), and a man who can feel what other people feel (mirror-touch synaesthesia). The fact that these disorders have medical names shows that these people are not unique: there is something reproducible and systematic going on here.

The colour-blind synaesthete tale sparks a question. The chapter starts off recounting an experiment demonstrating that people can’t actually see “auras”, and goes on to explain the particular subject’s perception of colours in terms of his synaesthesia. Putting these together: maybe most of those people who claim to see auras aren’t lying, aren’t con artists; maybe they are just mistaken, misinterpreting their own synaesthetic perceptions?

Several of the other chapters make me want to build some sort of unified brain model (I will resist the temptation). This thought initially started on reading Dennett’s Intuition Pumps, which made me wonder if blindsight recognition and Capgras delusion are just two sides of the same coin: emotional and rational perceptions being out of synch. Many of the descriptions here are similar: the brain is a mass of different models – rational, emotional, perceptual, proprioceptual, predictive, generative, and more – and it needs to integrate all of these coherently for “normal” cognition and feeling. If one or more of these models fails to be properly integrated, there appears to be something out of kilter with the world. The brain desperately tries to make sense of these contradictions, and “explains” the situation the best it can, with bizarre consequences. Different models failing to integrate give different problems, helping us understand how they do usually integrate. (So much for simple rational-only models of artificial intelligence.)

So there is much food for thought here, told in an accessible style.




For all my book reviews, see my main website.

Sunday, 19 April 2020

book review: Understanding Systems

Heinz von Foerster, Bernhard Poerksen.
Understanding Systems: conversations on epistemology and ethics.
Kluwer/Plenum. 2002

Foerster was one of the original cyberneticians. This book is an in-depth conversation between him and Poerksen, a journalist, probing his early life, life under the Nazis, later life in the US, but mostly his systems thinking and ((alleged) lack of) epistemology.

As I was reading this, I was firmly agreeing with parts, firmly disagreeing with others, and going do what? with the rest. The main thrust of Foerster’s personal philosophy seems to be that he wants to be epistemology free. Since everything is mediated through the senses, nothing can be known with certainty, and having arguments about whether something is “right” or not is fruitless.
[p40] If one just stops for a moment and says, “The person who is producing this view of the world is you. It isn’t outside, and it isn’t some so-called objective reality that I can relate to,” a very unusual emphasis on the respective personality of the person speaking occurs. All of the general statements that begin as “This is the way it is!” begin turning into statements that start with “I think that…” To return to rather lofty terminology, one uses the self-referential operator “I think” and decides not to use the existential operator “it is”. In so doing, a completely different relationship emerges that permits a dialog that is free and actually quite nice.
Although on the one hand this seems reasonable (I started writing “is clearly true”, but decided that was against the spirit of the passage itself), on the other hand, there are some things for which we at least have better evidence than others, even if that evidence is mediated through our senses and potentially unreliable. I have more evidence that I read this book (the notes I made while reading it, for example) than evidence that I understood it (the density of question marks in those notes, for example). We may be mistaken about the quality or provenance of the evidence (maybe somebody else made those notes; maybe I am hallucinating them), but if we treat everything on the same level, we would probably soon be hit by a car, or starve to death.

And what do you say when your conversational partners asks why you think X, asks for that evidence? If you always say “Oh, I have no evidence, I just think X”, your partner will soon stop arguing with you; you have to lay out your evidence. But Foerster doesn’t seem interested in presenting evidence, only in engaging in dialogue. I’m not sure what the purpose of the dialogue is, in that case. (This is presumably one of the bits I have not understood.) It also assumes that the person you are in conversation with is arguing in good faith, which is not always the case.

Anyhow, there is a lot of this sort of discussion, but at one point Poerksen calls him a constructivist, and Foerster replies:
[p43] No, no. I am Viennese. That is the only label that I have to accept. I come from Vienna; I was born there, that’s an established fact. Of course, you are correct when you say that there are a few people who claim that I am a representative of a certain epistemology. But that just isn’t right. I don’t have any epistemology at all.
Umm. How can Foerster claim that the “fact” of him being born in Vienna is “established”, or that Poerksen is “correct”, if he doesn’t “have any epistemology at all”? At first, I assumed this was a going to be a little joke, but it was never picked up on.

Despite these occasions of apparent self-contradiction (and who doesn’t do that?), there is a lot of food for thought in here, and interesting material on the dawn of the cybernetic age.



Wednesday, 15 April 2020

film review: The Man from Earth (2007)

John Oldman is a respected university professor, who resigns just as his career seems to be in the ascendant. He tries to sneak away, but his friends drop round to his cabin to throw him a farewell party. They can’t understand why he is leaving, and pester him for a reason. Eventually he agrees to tell them: he’s an immortal Cro Magnon who has to keep moving on since he doesn’t age. Initially his friends assume he is joking, but as the story lengthens, they start to think him mad, or maybe even start to believe him…

This is almost entirely dialog taking place in a single room, and is utterly gripping. Is he joking? As he and his friends point out, there is no way to prove what he is saying. But the story keeps building. One thing that makes John sound so believable is the serene way he both tells his story, and reacts to the jibes and questions of his friends. Could only someone who has lived as long as he claims, and been taught by the teachers he mentions, be so mellow?

Although filmed in 2007, this was conceived and written by Jerome Bixby somewhat earlier. I think that, with today’s technology, some of Oldman’s claims could indeed be substantiated: a DNA test might help demonstrate his stated age; some antibody tests might help demonstrate he had suffered the various ancient diseases he mentions. So he is even more right to keep hidden!




For all my film reviews, see my main website.

Tuesday, 14 April 2020

Covid-19 diary : online ordering

Went onto Amazon to order more of a consumable item that I’ve been buying for a while now.

Click Add to basket, quantity 1

Error message: Minimum order 2.
The item appears in my basket, but with quantity zero.

Increase the order quantity to 2.

Error message: This seller has a limit of 1 per customer.
The item now appears in my basket with quantity 1.

Proceed to checkout.

Error message: Minimum order 2.
The item now appears in my basket with quantity 2.

Proceed to payment.

(At least it didn’t get into a loop.)



Monday, 13 April 2020

book review: Complexity: a very short introduction

John Henry Holland.
Complexity: a very short introduction.
OUP. 2014

When I saw that John Holland had written “A Very Short Introduction” to complexity, I was excited, and snapped up a copy. Given Holland’s stature in the field, I was looking for a good distillation of concepts, and, maybe, a suitable introduction for my students.

Unfortunately, I cannot recommend this book. This is for two main reasons. Firstly, it is riddled with errors. Secondly, the part on Complex Adaptive Systems, or CAS (as opposed to the somewhat simpler Complex Physical Systems, or CPS), appears to be a summary of Holland’s own work in the area, not the more general introduction I was looking for.

The first issue is more of a problem. Here are a few examples. On p.7, Holland discusses von Neumman’s cellular automaton (CA) replicator, a complex pattern that can replicate itself, then references figure 1, which shows a glider from Conway’s Game of Life CA. On p.11, he says that CPS tend to be modelled using partial differential equations (despite most of his examples being discrete space and time CAs), then states that the theory of partial differential equations (PDEs) is additive, that is, linear (and says this again on p.25); by p.13 he is talking about PDEs being used to describe chaotic (necessarily non-linear) systems. On p.15 he states that the Koch snowflake fractal curve is “everywhere discontinuous”, rather, it is everywhere continuous, but nowhere differentiable. And so on.

Okay, so maybe the part on CAS is better than the part on CPS, because that’s his area of expertise? But no. Take figure 6, which has two parts, one a set of rules, and the other supposedly a network representation of the behaviour of those rules. Except that the two parts don’t fully correspond, and the hash notation in the rules (a wildcard) is nowhere explained; the figure as it stands is unintelligible. Furthermore, this specific formulation of rules is Holland’s own model of CAS, which would be absolutely fine in a book about his model, but not so much in a general introduction.

I gave up reading soon after this point. Even if there are some interesting insights (and I’m sure they must be) how can they be picked out from the mass of erroneous statements, and the potentially over-specific model presented? Unfortunately, this book will have to go back on my shelf; I will not be recommending it to my students, or to anyone else.




For all my book reviews, see my main website.

Friday, 10 April 2020

Covid-19 diary : bats

Today I learned that there are over 1200 species of bats, and that they make up about 20% of all mammal species.

So, one fifth of all mammal (species) can fly!





Tuesday, 7 April 2020

Covid-19 diary : pollution

So, the Covid-19 lockdown has reduced pollution noticeably, in more ways than one.

Less smog in China, less NOx in Europe (but unfortunately not dolphins in the clearer Venice canals).

And, something I’ve recently noticed – no spam phone calls!


Monday, 6 April 2020

correcting proofs

I’ve spent a couple of hours correcting proofs of a paper.

There were several … interesting … changes made by the typesetter.

But the one the really had me yelling at the screen was in some mathehatical text.  We had introduced an operator called redacted (well, it wasn’t actually called that, but I’m protecting the guilty here).  We consistently used a sans serif font, to distinguish it from other terms.

In some places it had been changed to redacted.  In some places it remained as redacted.  And in other places it had been changed to redacted.

Aaaargh!!!



Sunday, 5 April 2020

Bach, the Universe & Everything

I was supposed to be in London today, giving a talk about Can a Bacterium Compute at the Orchestra of the Age of Enlightement’s “Bach, the Universe and Everything” event.

However, *gestures vaguely at world*.

The guys in charge organised a virtual event instead.  I recorded my talk, which was a quite straightforward process, just requiring a webcam, a stepladder and a tripod.  More impressively, the orchestra performed remotely, and individually.  I assume each part was recorded separately, then mixed together for the broadcast performance.  I rather like the montage of individual performers: you can see who is doing what, very interesting.


With the power of the web, you too can indulge in this virtual event, timeslipped from its original release.  This might even reach more people than the planned live event would have.