Emergence 103
| Emergence - The connected lives of ants, brains, cities and software | |
| author | Steve Johnson |
| pages | 288 |
| publisher | Penguin |
| rating | 6 |
| reviewer | Jim Richards |
| ISBN | 0-713-99400-2 |
| summary | Seeing order and patterns in apparent chaos. |
This book covers the theory of emergence, which states that within a system of what seems to be anarchy, there are underlying rules that govern the pattern of behaviour and bring order out of chaos.
This books serves as an introduction to the field of emergence. It is something that is already happening around us, but we usually cannot see. The reason for this is that you need to look at a higher level then the individual organism. Ants can not see the society as a whole that they are members of. Just as we humans may have an understanding of the local community we are in and of ourselves, we need to step outside (or above) the city to understand how it functions. A city, like an ant colony does not have rules from the top as such, but rules that each occupant obeys, and it is these rules that give order to the chaos and make the resultant community behave like an organism as a whole.
I really wanted to like this book. But the level of information within it will make me put in into the light, popular fiction section of my bookshelf. One of the aspects of the book that really wanted me to give a good review is that the author makes a good introduction to the theory behind the comments system of Slashdot, the way people are chosen to rate comments and how good comments filter to the top. As such, I would have liked a review of the editorial process on Kuro5hin as well, since the two systems as fairly similar. In fact, I think the Kuro5hin system is better, because long time readers will see that the stories have moved away from an open source/linux focus to more cultural aspects, thus reflecting the change and growth of the community. But the idea of a Daily Me portal, that serves information that would suit us is explored heavily.
As I read the book though, an uneasiness came upon me, just as I do when reading books on neo-Darwinism. There is no mention of where these rules as such come from except through evolutionary survival or initial chance. If anything, the author implies that we are in a universe that had the initial conditions set, and left running. So we'd evolve or grow into who or what we are.
The idea that a God figure could be there, tweaking the parameters as the model runs, or even setting the initial conditions works against his ideas. This view is however explored in the chapter Control Artist, where the author comments on the development of software models, notably computer games. Games such as SimCity are discussed where the rules are set, but as a player we get to choose what gets built, what gets destroyed. Although here we are playing the Mayor of the City, the notion is the same; we control the macro level and not the micro level. But at the micro level, the software developer who built the game in the first place controls each inhabitant. Nothing really, is left to chance. Given the exact same initial conditions and same set of instructions the computer will create the same environment.
So, like most popular science books currently available it will educate you, entertain you and keep you occupied while reading it or totally bore you. But it is not a book of philosophy to base life on, which thankfully, the author has not tried to provide. It is very well researched, and the author seems on top of current trends and ideas. His writing style jumps around quite a bit, and some of the connections between topics might seem a little far fetched but it is an entertaining read as an introduction to the field of emergence theory.
Pet peeve 1: Notes. The notes section at the end is fairly extensive. But there are no foot notes in the book. The notes are indexed by page and quote. So as a reader you have to constantly check the notes section to see if there is a note or reference for the page you are reading.
Pet peeve 2: There was (for me) a glaring technical error on page 120.
You can see who is visiting your site, unless they are using an anonymizer proxy, or other system to hide your headers. The HTTP-REFERER header gives you exactly this information."Ironically, it is precisely this feedback that the Web lacks, because HTML-based links are one-directional. You can point to ten other sites from your home page, but there's no way for those pages to know that you're pointing to them, short of you taking the time to fire off an e-mail to their respective webmasters."
You can purchase Emergence at Fatbrain. Want to see your own review here? Read the book review guidelines first, then use the web submissions form.
Referrer tells you who's following the links (Score:5, Informative)
Re:Referrer tells you who's following the links (Score:1)
Well, there's always google: try a query for link:your.link.here. It will return a list of pages that link to your link. It's not inherent to HTML, but it's a way, and without need for referers.
Re:Referrer tells you who's following the links (Score:1)
Bzzt! The referer header tells you the URL of the document containing the link. It tells you nothing about who followed the link. A referer header can be forged, but otherwise there actually is a link and it is contained in the document whose URL is in the referer header.
Re:Referrer tells you who's following the links (Score:1)
But the point is that you never know the links that exist, only the ones that are followed. In this sense linking is one-directional.
Searching google for links is another matter, but it's not a "glaring error" to claim that linking is one-directional. Debatable is a more appropriate word.
Akward phrasing, simple message (Score:1)
I think you misunderstood the comment. He meant that you only receive information on those links that people follow. A hundred pages could link to your site, but if nobody ever follows those links, you'll never know they exist.
The subject of his message may have been confusing. But if you read the rest of you'll see that he didn't imply that HTTP-REFERER gives you additional information about the person who followed the link, it only provides the URL of the page they came from.
Re:Referrer tells you who's following the links (Score:1)
HTML links which use the A element are unidirectional primarily because they are embedded in the source document (the webpage at the start of the link).
There is a branch of hypermedia research which deals with what is known as Open Hypermedia, in which links are objects which exist independantly of the documents that they link. This allows more complex link types, such as bidirectional or n-ary (many-ended) links, and promotes a degree of flexibility in the hypertext because links may be applied to many different documents (simplifying link maintenance).
Because the links are stored separately from documents, the resolution of links can be performed both forwards (when following a link in the normal manner) and backwards (when asking "what links point at this page?") with equal ease. The relative paucity of the Web with respect to this type of links has historically been an issue in the hypermedia research community, and it is due to this that the W3C has taken steps to rectify the situation by introducing the XLink [w3.org] recommendation, which allows the creation of open hypertext links.
Regarding Pet Peeve #2 (Score:2)
If no one clicks on the link to get to the page, you will never know the link exists. Do those links matter? Probably not.
Re:Regarding Pet Peeve #2 (Score:2, Informative)
Re:Regarding Pet Peeve #2 (Score:1)
The point being made in the book, I believe, is about Google. It uses the phenomenon of linking in order to rank sites. There is no "master thinking program" analyzing page contents to determine similarities. Rather, each page's links (and the text they use to link) come together (in Google) to "self-select" similarities. That a larger taxonomical "intelligence" emerges from the individual phenomenon of linking is evident from how damn right Google gets its results.
Sure the links matter (Score:2)
How else can you sue people for accessing your content in 'inappropriate' ways?
If someone came to a deep page without first going through the 'EULA' page, or some other crank..
[/sarcasm]
Re: (Score:1)
Re:Regarding Pet Peeve #2 (Score:1)
Re:Regarding Pet Peeve #2 (Score:1)
Hey, this is my first
One Hand Clapping (Score:1)
re hyperlink (Score:2)
Technically this is not true. The HTTP-REFERRER only shows you who sends people to your site by a link, not who links to it. Just because you can tell where someone came from doesn't change the structure of a link. The link its self is truly one way.
Order from chaos... (Score:2)
By the way, did anyone else notice that this review sounded more like a school book report than an actual review? The guy who submitted spent an awful lot of time pointing out stupid "technical errors" (they weren't errors, by the way) to really lend any plausibility to his review. Just a thought.
Re:Order from chaos... (Score:5, Informative)
The canonical example of this is flocking, from Flocks, Herds, and Schools [toronto.edu] by Craig Reynolds. Basically, if all members of a group avoid collisions (with obstacles and each other), match velocity with locally perceived group members, and stay close to local members, a flocking behavior is achieved. There is good evidence as well that this is how flocking is achieved in nature -- ornithologists (bird people.. may have gotten the word wrong:)) have studied Mr. Reynolds' simulations and found them to be indistinguishable from birds.
Another example is ants finding their way to food. They start off randomly travelling, leaving their pheremone trails everywhere. However, once food is found, the pheremone trail to that food is reinforced over and over, causing more and more ants to travel there. Eventually you see a line of ants going straight for the food -- all because of a "wander unless I sense enough pheremones" behavior.
The point of this is that emergence is not necessarily a global phenomenon -- it occurs at all levels.
Get the flock out of here... (Score:1)
Re:Get the flock out of here... (Score:1)
-- Your body is just a flock of cells flying in close formation.
Re:Get the flock out of here... (Score:1)
Re:Get the flock out of here... (Score:1)
Re:Order from chaos... (Score:1)
Re:Order from chaos... (Score:1)
Re:Order from chaos... (Score:1)
I think if the initial conditions were a bunch of motionless birds suspended in the air then the next thing to happend would be synchronised plummet as they wonder who the fuck was doing thought experiments on them. I guess they would eventually swarm around a lower point, unless they impacted first.
Just ignore me.
Re:Order from chaos... (Score:1)
I'm not saying that Emergence is that. I'm saying that that's what the book identifies as being the way to observe it.
You haven't read the book, but your idea about emergence is only half way to what the author is trying to identify. It is about the behaviour of individuals within a community, and how that community appears. The emergence behaiour can only be seen at a macro-level, not at the individual member level.
Re:Order from chaos... (Score:5, Funny)
20 years of USENET archived, and we still ain't seen it.
Re:Order from chaos... (Score:2)
Good point!
A couple of years ago I was fortunate enough to attend a lecture series on emergence by Prof. Benoit Mandelbrot. When he talked about clusters of galaxies, he posed the problem: 'Are the patterns out there, or are the patterns only in our minds?' In nature without conscious observers, there are no patterns - because there is nobody to define clustering or other patterns. And if we define 'order' in a different way, we start seeing different things.
It seems that the human vision is inherently 'tuned' to see certain kinds of order in everything, and it has probably been useful over the course of evolution. There are several stories of people who have seen the face of Christ on a randomly colored surface. Sometimes when meditating, I stare at the carpet and see weird forms emerging. In the million-monkey experiment, you probably start to see interesting stories way before the emergence of a grammar-proofed Hamlet.
Re:Order from chaos... (Score:1)
But that's not really what emergence is. Emergence is large scale behavior that is not built into the small scale rules. Traffic, for instance, is an emergent behavior. There is nothing in the descrption of a single car driving around that makes traffic necessary. However, certain conditions will invariably lead to it's development.
Emergence is nested all the way down, in every physical system. Society is emergent from individual behavior. Individual behavior is emergent from biology. Biology is emergent from chemistry. Chemistry is emergent from physics. Physics may be emergent from the fundamental law of the universe. I might just have to buy this book.
Not all infinities are created equal (Score:1)
Not enough superstition? (Score:2, Funny)
You can hardly blame the author for writing a popular science text that fails to include wild speculation about the influence of medieval superstition on physical phenomena. I imagine he probably failed to consider phlogiston and the luminiferous ether, too, but I would have a hard time holding that against him either.
Re:Not enough superstition? (Score:2)
One Google to find them (Score:2, Informative)
Er, interesting review.
I googled and filtered, an intro to Emergence the notion, [mit.edu] and an excerpt from Emergence the book. [nynma.org] (In which Slashdot is discussed.)
Oh, and here's a less interesting book review of Emergence from the Village Voice. [villagevoice.com]
Interesting, but populist and agendad. (Score:3, Insightful)
The primary problem is that rather than being a popular science book, it comes accross as a populist one, picking easy pop-culture references rather than more appropriate ones. This would be more forgivable if the book was giving a more balanced view of the subject, but the author seems to have a definate agenda which he is trying to communicate rather than giving a solid, unbiased view of the topic.
A good book on the subject for people who have no knowledge of, or interest in, the topic.
a content-free author (Score:2, Insightful)
(the fact that most of the comments are clarifications on the HTTP-REFERRER discussion seems to suggest that the book might not terribly engaging to the Slashdot audience anyhow.)
there you go (Score:1)
1-Way Linkage (Score:1)
The Self-Made Tapestry Pattern Formation in Natur (Score:4, Informative)
A more serious alternative to Emergence might be The Self-Made Tapestry: Pattern Formation in Nature [santafe.edu].
Thinking about emergence (Score:2, Interesting)
I think of emergence in terms of complex behavior resulting from simple rules (eg. the many kinds of human thought resulting from the interactions of a pile of simple neurons).
I think of emergence in terms of "the whole is greater than its parts" rather than "there's order in chaos".
Re:Thinking about emergence (Score:1)
This is a nice way of thinking emergence, and a very useful one even in plain old classical physics. For example, the macroscopic properties of matter, such as temperature, are emergent in the sense that a lower level description of the system can be discarded. Temperature is not really a property of any of the system's parts, but one of the system as a whole. Temperature, pressure and such are a result of the collective behaviour of the molecules, and in systems where the interaction between the parts (molecules) is significant, the resulting behaviour is complex.
I think of emergence in terms of "the whole is greater than its parts"
I don't really like this phrase, or the variant "the whole is greater than the sum of its parts". The one I mention is more evil because it uses a very specific mathematical concept "sum" in a very vague manner. But it is clear that if I take the parts of a car, for example, and stuff them into a box, they're not a car. They are the parts of a car. I don't see what's the deep philosophical insight in a phrase like this. It's just stated in a mysterious way to conceal the fact that nothing has really been said.
On the other hand, "The whole is equal to its parts and their interactions" sounds a lot less flashy.
Re:Thinking about emergence (Score:1)
Re:Thinking about emergence (Score:1)
On the other hand, "The whole is equal to its parts and their interactions" sounds a lot less flashy.
Exactly. From your observation, an Axiom:
Re:Thinking about emergence (Score:2)
And that was from my old Systems Analysis class, ten years ago.
Pretty shallow - try "Turtles, Termites..." (Score:5, Informative)
Re:Pretty shallow - try "Turtles, Termites..." (Score:1)
Re:Pretty shallow - try "Turtles, Termites..." (Score:2)
Sort of. It's Logo with thousands of turtles running at the same time (in 2-D). Intial implementation was on a Connection Machine.
Re:Pretty shallow - try "Turtles, Termites..." (Score:2)
As the prior poster mentioned, StarLogo is a "massively parallel logo" -- a language inspired by Logo and retains Logo's coneptual simplicity. The goal of StarLogo's design was to create a tool in which to explore emergent behavior and decentralized thinking, yet remain a very accessible and fun environment.
Emergence (Score:3, Insightful)
I've read several popular items on artificial life, chaos, evolution, etc. All of them delve into this concept of emergence: this notion that totally unexpected - but organized - behavior can result from the complex interactions of very simple rules.
The peculiar thing about emergence, though, is that all these authors and researchers are fascinated by it but nobody seems to have a rigorously measurable definition. Nobody seems to be able to say that "if and only if X and Y happen, then you have emergence."
Has anybody here seen such a definition?
Re:Emergence (Score:1)
If you have many simple units preforming behaviours built on simple common rule-sets, who all interact together, and react to these interations according to their rule-sets, and a macro-behaviour occurs (something that none of the individuals would be able to do by themselves) this is Emergent behaviour.
Re:Emergence (Score:1)
That's the thrill of science. (And most of it...) Something nebulus on the horizon like, the seven cities of gold, you know its out there but you can't quite put your finger on it, so you cast out on various paths to see what you come up with.
Emergence is very new, as in <30 years old for really serious studies (I'm sure people were contemplating it before then, but not really analyzing it at all) I mean just as short as 100 years ago we still thought simple math would solve every problem.
This particular branch is exceptionally interesting because it seems to have character in a VAST number of disciplins and possible all of them. That the character of emergence, if boiled down, could be of pragmatic use in all sciences. Very cool (not to mention everyone's guess about emergent intellect.)
Nathan.
Re:Emergence (Score:1)
Re:Emergence (Score:2)
Thousands o (Score:1)
Theologians work for centuries to finely craft their ideas about God.
And the best you can come up with is, 'He's the Mayor from Sim City.'
I hate the fact that scientific papers never say, "God did it. We don't have to bother with this anymore, it's just too complicated."
Re:Thousands o (Score:2)
It's because scientists have the perseverance, and the _belief_ that human reasoning is a sufficient tool for obtaining any knowledge, even the ultimate truths. IMHO religions based on 'fixed truths' are a reflection of mental laziness. When I see people sweeping problems under the rug, just by saying 'it's God's work and we should leave it as a mystery', I get a feeling that they are (a) afraid of truth, or (b) lacking the self-confidence to go out and explore the problem. The latter can easily translated as mental laziness, a closed shell of comfort.
In effect, if you believe that in the end it is a mystery which should be left in peace, you should not even start any scientific study, much less write a book about it. I think every question 'Why?' will eventually trace back to one single question: 'Why does the universe exist at all?' If you can say 'Because God did it', then the same answer can be applied to any other scientific problem. Which of course means that there would be no science.
Let me emphasize again: Science is all about optimism, the belief in yourself - that we as humans have the mental power to understand nature. As such, this is in no contradiction with Christianity or similar religious ideas. But with enough confidence, who needs a god anyway? ;-)
Re:Thousands o (Score:1)
Author interviewed on NPR (Score:3, Informative)
--Zone Dancer
Re:Author interviewed on NPR (Score:1)
Re:A New Koan (Score:1)
Been there, done that... (Score:2, Informative)
More useful than the reviewer gives credit for (Score:1)
Bioligists discuss it in terms of evolution, physicists talk about it in terms of particle physics and cosmology, sociologists talk about it in terms of city formation and anthropologists in terms of cultural dynamics. But none of them try to explain emergence in and of itself, except for the mathemeticians (and good luck figuring out what the hell they are talking about if you don't have a higher degree in pure math).
As a prior commenter stated, many people *talk* about emergence, and derive emergent principle from their disciplines, but very little effort is made to define what emergence is, how it works, and how to tell the difference between emergence and random noise. In answer to another commenter's question, emergence frequently *is* a matter of scale, random behaviour at one level displays emergent properties at the next level, then reverts to apparent randomness at higher scales, and then can display randomness *again* at the next jump in scale. Emergence is what happens when all the "random" fluctuation happen to cancel each other out in just the right ways to make something definitely non-random happen.
That's why this book is useful, because it examines emergence as a whole concept in plain english, rather than just focusing on a particular example or type of emergence.
--Dave Rickey
I read it, and... (Score:1)
I thought about the fact that one could look at the referer data from a web server to make http bi-directional, but I think that for any kind of emergent behaviour to come about, one has to have many individual units all behaving in similar ways, so even if one or two people were to hook in some smart web scripting that looks at, and reports who refered to them, it wouldn't make a difference unless a large critical-mass of individuals did the same thing. So HTML over HTTP in it's present incarnation is not bi-directional for all practical purposes.
The reviewer doesn't seem to like the idea of micro evolution without the intervetion of God,
Could be, but this is a book based on scientific theory, so you can't really blame it for not showing a creationist side of the argument.More than anything, this book made me want to go out and write some cool internet client/server that would do some very simple, known, micro-behaviours but if distributed widly around the internet, and interacting in various ways, they would produce, undefined, Macro Behaviour! That is what Emergence Theory is all about, if I understand it correctly. Same thing that's happening in the brain, Neurons are doing very simple micro-behaviours, but put them into a great big hunk of brain where there are millions of simple units interacting and doing micro-behaviours (fire-nofire) extreamly intelegent and unpredictible Macro-behaviours occur.
This book got me all excited because this was the first time this was explaned to me in a simple way using analogies that I understand, like software, games and even Slashdot! I recomend it, Steve Johnson is also the author of "Infomation Culture" which is apparently a pretty good book too, I havn't read it yet.
yebbNOSPAM@kidojo.com
Re:I read it, and... (Score:1)
As for the reviewer's angst about the failure to explain God's role, I'm surprised the same thing didn't jump out at him that did at me: Emergent systems are controlled from the edges . Direct intervention rarely produces the results you are looking for, you have to monkey with the fundamental rules.
God's all-powerful and all-knowing, but he worked himself out of a job in the first planck unit after the Big Bang. Since then, there's been nothing for him to do but sit back and watch it run.
--Dave Rickey
A similar book: Complexity (Score:1)
The other "Emergence" was much more than a 6 (Score:3, Informative)
It's hands-down the best post-holocaust SF I have ever read, but it is, incredibly, out of print. If you like this sort of SF, it's worth tracking down a copy.
Unfortunately, the author wrote one more book, "Threshold", and then disappeared entirely. I don't know whether he passed away, ditched writing, or what, but it's a shame.
Re:The other "Emergence" was much more than a 6 (Score:1)
--Dave Rickey
Additional reading... (Score:4, Informative)
If you are looking at some additional texts in the area, Dr. John Holland has written two books. (Holland is also a MacArthur award winner, which places him in some fairly good company.)
- Emergence : From Chaos to Order (Helix Books)
- Hidden Order : How Adaptation Builds Complexity
I thought /. reviewed one of the books earlier, but a quick search did not find anything. As I recall, Emergence is the earlier book of the two and is much more technical. Hidden Order is more topical and discusses concepts as opposed to technical details... but it has been a few years since I read either.
Just some info for those who might want another angle on a similar subject.
Re:Additional reading... (Score:1, Informative)
This book is well though out, fairly well organized and avoids using 'populist' examples in favor of examples that easily demonstrate the concepts without stretching the imagination.
-Chris
EGB (Score:4, Insightful)
Re:EGB (Score:1)
Bias (Score:1)
Or, with equal logic, "it is not a book of programming style and architecture to base applications on, which thankfully, the author has not tried to provide."
What's the point in saying that it isn't something it doesn't claim to be? So you were hoping for support of your personal beliefs and didn't get it? To bad. That isn't a reason to go from saying that the book will educate the reader (in the quote above) to calling it fiction:
I really wanted to like this book. But the level of information within it will make me put in into the light, popular fiction section of my bookshelf.
StartRant:
:EndRant
A belief system must be pretty desperate for support when a science book gets relabeled to fiction, not for an attack, but merely for failing to provided the support the reviewer had hoped for.
Sorry, but wrong (Score:1)
Referrals only tell you what people came to your site _from_ a said site, not if a link exists or where the link is.
Think about:
- use of a link redirection page by a site (usual in corporate sites, etc)
- links that exist but aren't followed
- people that surf with referrals turned off (lots of software allow this)
The link system is effectively one-way only.
Two-way links were proposed in the original Xanadu system, but no provision exists under the current www scheme. Except, of course, for google...
A shallow review of a shallow book (Score:5, Informative)
That is not to say that Emergence is a good book. It is an adequate book to give to a lay reader who is completely unfamiliar with the subject matter so that they can at least understand the basics of emergent behavior. On the whole the book is about at the same level as Kelley's Out of Control, cute but nothing of consequence. Anyone who is really interested in this subject should start with the following list:
Turtles, Termites, and Traffic Jams (Michael Resnick)
Emergence (John Holland)
Hidden Order (John Holland)
At Home in the Universe (Stuart Kaufman)
A Self-Made Tapestry (John Ball)
Swarm Intelligence (Bonobeau et al.)
The Computational Beauty of Nature (Flake)
Anything (and everything you can find) by Dawkins, E.O Wilson, and Hofsteader along with the Artificial Life series from the Sante Fe Institute (preceedings from the conference series of the same name)
This is an interesting and important subject area which most Slashdot readers would be well-served to examine and explore. Unfortunately such exploration is not served well by either this review or the book being reviewed.
Re:A shallow review of a shallow book (Score:2, Informative)
Re:A shallow review of a shallow book (Score:1)
Emergence is an adecuate book for someone who does not know anything about the subject. For such a profile it could be big eye opener. However for those who were expecting more concrete matters, it was shalow and lacking substance.
I can recomend "The Timeless Way of Building" by Christopher Alexander. Even when this book talks about architecture, it touches in very insightfull ways on emergence, patterns, and self orgaization.
F.
Steven Johnson's background (Score:1)
I read this book when it first came out and I've been working on a review of it myself. I figured it was an ideal candidate for a review on /. given Steven Johnson's (the author) multiple referrences to /. in the book. It is interesting to note Johnson's background in the context of site many Slashdotters used everyday. Johnson was a founder of now dead community generated content sites Feed Magazine [feedmag.com] and Plastic [plastic.com], which are very similar to /. in the way they are generated an community maintained. Plastic even uses Slash [slashcode.com] as its base. I found the sections pertaining to how sites like these work to be very insightful and they'd probably be of interest to anyone who's ever wondered why /. works as well as it does.
Additionally, our reviewer leaves out the parallels between biological emergent systems (slime molds, termites, etc.) and computer systems. Johnson gives an entirely new deconstruction of the 'pacemaker' or 'queen ant' theory in both computer and life systems. Altogether, I think the book is worth the 3 hours it takes to read.
The Origins Of Order (Score:1)
"The Emergence of Consciousness" (Score:2)
is it scientific? (Score:2)
complex behaviors results from simple underlying
phenomena. For example Mandlebrot fractals are a
six line program in FORTRAN. Human mental activity
arises out a trillion elementary nerve cells, etc.
The problem is, this is unpredictable.
By definition science is repeatable experimentals
and observations.
So emergencent phenomena are not predictable until
that happen, and therefore non-scientific.
Re:is it scientific? (Score:1)
However, you are correct in that most of the examples you see in cited in books are just toy models. Interesting, but they don't tell us anything useful about complex systems.
Another book, and Swarm (Score:3, Informative)
By the way, people interested in this stuff may be interested in checking out the Swarm [swarm.org] simulation system, a multi-agent simulation environment. Some of the demos that come with it are the ant/pheromone models and so on, which e.g. Resnick also explored in StarLogo.