Sunday, August 17, 2014

The Initial Condition in the Tabletop Critters Model

This post will start a longer expression of  the model of Tabletop Critters which I presented a few months ago.  The model of tabletop critters, you may recall, is one implementation of the general Resource-Patterns Model of Life.  Tabletop critters show consequences which seem strikingly important to me.  But it seems that I have failed in the past to convince my readers about these consequences. So now I will add drawings and a more careful explanation of some points.

We imagine a world which is a flat surface, a little section of tabletop works well.  On the tabletop we find little living things which we call critters.  We might think of critters as single-celled organisms, but their size is not particularly important.

Preliminary List of the Properties of Critters
What is important is that these critters have certain properties which we would associate with living things. (The following list is adopted for critters from the general case for Living Things which was described in this post.)
  • The critters can survive only if they get adequate nutrients, water and sugar. Fortunately there is some water and sugar available in this environment, about which we will learn more later.
  • The critters can sense their immediate surroundings, noticing if they are nearby to water, sugar, or another critter.
  • The critters have a memory and can use it together with sensory inputs to decide (to calculate based upon some rules) upon an act to attempt.
  • The critters can act in various ways. They can move about.  They can consume water or sugar that they find within reach.  They can reproduce by dividing when their internal reserves of water and sugar are adequate.
  • The critters have motives, they try to survive and to accumulate internal stores of water and sugar to improve their chances of reproducing.
  • Time passes in this world and for the critters we model the passage of time in increments. In each time increment a critter can attempt to perform only one act. First, before that attempt, the critter senses its surroundings and internal conditions, then it searches in its memory to see if it has ever encountered similar conditions. It "thinks" as well as it can with the mind we have specified for it. Finally, it decides which act from among its capabilities to attempt.
  • In each increment of time a critter's body consumes some of its stores of water and sugar. The critter dies if one of these stores runs out.
We have critters as just described in our model world. In this world we also find occasional deposits of water and sugar. So we have an ecology in which it is possible for the critters to survive.

Symbols representing the three types of objects in our world

Additional Properties of Critters
As I have worked with this model, trying to make it run in computer code, I have continually discovered more properties which I had to specify in order to make the model achieve what I hope. One property is the distance a critter may move in each time increment. It may move a distance roughly equal to the diameter of its body (the yellow oval).

Critter movement

A critter may move in each time increment in any direction in the plane provided its body does not collide with anything, a resource or another critter's body. In order to preserve the visual clarity of the model, objects are not allowed to pile on top of each other in the plane.

Critter sense area inside dotted oval
The seven rays extending outward from the citter's body suggest the sense area. The dotted oval above shows this area. A critter can sense the presence of another object in its sense area but not anything outside that area. So in this picture it can sense the spot of sugar but not the drop of water.

A critter can attempt to consume a resource which it can sense in its sense area. It is not necessary that the critter move closer, for the purpose of consumption, so its body is adjacent to the resource. A critter cannot consume a resource outside its sense area. In the picture above the critter can attempt to consume the sugar but not the water.

A critter does not always accomplish what it decides to do. In each increment of time it decides upon an action to undertake, then it attempts that action. But larger fate determines whether and how much the critter's attempt succeeds. For example two critters may move in one time increment to where both can sense a single water drop. Both may decide to consume the whole drop with their next act.

Critters cannot always succeed in their attempted actions
In the picture above, both critters attempt to imbibe the water drop at time n+1. But obviously both cannot succeed. So the program running the model plays the role of Fate and somehow decides how to allot the water in the drop.

The Initial Condition
We start with an initial condition in which a small population of critters just barely survives by foraging for water and sugar. There is no steady and certain source of water or sugar. Instead a small portion of water or sugar appears now and then, randomly dropped into the world. These resources come as gifts from fate perhaps, or are carried in by the wind. In any case the critters' only hope of survival comes from moving about almost continuously in hope of encountering water or sugar. The critters are hunter-gatherers. Death because of starvation for either water or sugar is their most common fate. But fate can also be good sometimes.  Sometimes a critter finds enough water and sugar to enable it to reproduce. So the population hangs on — barely. In our initial condition the population of critters is near the maximum that the environment can sustain, given the rate of influx of resources.


Initial condition: critters foraging randomly
Note about sizes of objects in these pictures: I vary the sizes of critters and resources in these pictures in order to make each picture as effective for the purpose as possible.  As we zoom out to show a larger piece of the world I will sometimes have to increase the relative size of objects which initially appeared to be the smallest in order to keep them from becoming too small to recognize.

This completes our description of the initial condition in the model of tabletop critters. In a later post we will see changes in which the critters start to live richer lives. The images will remind us of prosperity which can grow in human communities, as I will try to convince you.

Wednesday, August 13, 2014

Looking for RPM's Cousins

The Resource-Patterns Model of Life RPM will probably seem alien to most economists. But it might have close cousins in two other fields: multi-agent modeling and gaming.

Multi-Agent Modeling
RPM falls into the field of multi-agent modeling (also called Agent Based Modeling). I have looked quickly into the literature of that field and attended one conference*. I have not found anything which I recognized as a parallel to RPM. But parallels might be there. One day I hope to look more carefully.

Also I have spent months coding and running parts of RPM as a multi-agent model. (I have a background in computer science.) The exercise has taught me a lot. But the results so far will not help me communicate what I believe is important in RPM. I may do better by calling to the intuition of the reader as I do in this blog  with English sentences and pictures which I create in a drawing program.

Gaming
RPM could be implemented in a game. Here again is a field with which I am unfamiliar. I have not played computer games much during these past 30 years. There may be games now that use RPM. I need to catch up. If you are a donor who would like to fund this research, please feel free to send me a letter of application.


* note added January 2016. That "one conference" occurred in fall of 2007 at Northwestern University, sponsored at least in part by Argonne National Lab, and (from my current search) was titled "Agent 2007 Conference on Complex Interaction and Social Emergence".  Now I have attended and reported upon another agent-based conference, in fall 2015 at Santa Fe, New Mexico.

Monday, August 11, 2014

A Relationship with Austrian Economics

This week I have finally started to read a book, The Economics of Time and Ignorance by O'Driscoll and Rizzo, which I have noticed referenced many times in my reading during the last five or ten years. Although I am still in the first chapter, I am struck this book may be more relevant to my work than any other book I have started for the past 15 years. I appreciate how clearly the authors state some of the precepts of Austrian economics. The authors clarify some views which have always been murky to me. But also I notice what is not in the book so far.

So I think I am seeing more clearly how this blog's theme, the Resource-Patterns Model of life (RPM*), can contribute to economic understanding and study. I think RPM adds axioms which are essential for a better understanding of social intercourse. I report that I have seen nothing so far in Austrian or mainstream economic literature which adds what RPM adds. While Austrian economics seems good to me, more useful for my ends than mainstream economics, still Austrian economics leaves big gaps. (You may safely assume that I am a biased reporter. :)

I continue to suppose that I need to write RPM as a book. I believe the book promotes a new Kuhnian paradigm. So the book will not pause in an attempt to establish a base of credibility in either mainstream or Austrian economics. Rather it needs to stand on its own, accessible to a curious layman. If I find readers who value RPM, these readers will probably not come from among established economists, although I will certainly be delighted if any established economists prove me wrong about this.

Perhaps there will be a chapter's worth of tie-ins with mainstream economics. After RPM is laid out and given many clarifying examples, I believe it will be a helpful exercise for me and other economists to revisit ideas such as market and equilibrium, to see how such ideas relate to structures we imagine in RPM. Indeed, once RPM is established in the mind of the reader, I hope that many old ideas will gain depth when seen from the direction of the new paradigm. Additional old ideas which will gain new perspective include: policy, firm, price, institution.

I plan to attend a meeting of Austrian economists in northern Virginia on October 2. Before that meeting I hope to have finished the book by O'Driscoll and Rizzo.  And I hope to have drafts completed for a few of the chapters of my fancied book on RPM.


* RPM.  While adopting this shorthand for my model, I recognize the precedent claims of both Revolutions Per Minute and Robert P. Murphy.