16. Emergent behavior¶

[status: content-mostly-written]

16.1. Motivation, prerequisites, plan¶

Purpose: a fun exploration of how complex large-scale behavior emerges from very simple rules on the small scale.

Prerequisites:

The 10-hour “serious programming” course.

16.2. Before you start¶

Watch some of the videos from Melanie Mitchell’s course “Introduction to Complexity”. At this time only watch the video for Section 1.1 (overall introduction to complexity) and all the videos for Section 6.3 (introduction to 1-dimensional cellular automata): https://www.youtube.com/playlist?list=PLF0b3ThojznRyDQlitfUTzXEXwLNNE-mI
Read the Nova slides on Everyday Examples of Emergence (4min) http://www.pbs.org/wgbh/nova/nature/emergence-examples.html
Watch the video “How do schools of fish swim in harmony?” (6min) https://www.youtube.com/watch?v=dkP8NUwB2io

16.3. Write the simple-ca.py program which implements a cellular automaton¶

See the separate source code at URL

https://sites.google.com/site/santafecoding/documents/simple-ca.py

You can copy this program in, or you can download it and ready through it to understand how it works.

16.4. Install and run the golly program¶

Command line: type “golly”, it will tell you how to install it. Experiment with drawing your own initial cells and use TAB to advance one at a time, or the run button to advance more.

Then explore the library of starting positions, specifically:

Life -> Guns -> 2c5spaceship-gun-p416

Life -> Guns -> golly-ticker

16.5. Further study¶

16.5.1. Play with the simple-ca.py program¶

Make modifications to simple-ca.py to make it

Run longer runs so you can see more of the patterns.
Have more cells in each row – make it as wide as your terminal will go.
You will find the following lines of python code in simple-ca.py:

new_row[i] = new_cell(neighbors)
## NOTE: new_cell_with_rule() is part of the extended code (at
## the bottom)
# new_row[i] = new_cell_with_rule(neighbors)

comment out the line that sets new_row[i] to be the result of new_cell(), and uncomment the line that sets it to be new_cell_with_rule(). Then look at the code in new_cell_with_rule() and play with setting different rules and seeing what the cellular automata look like.

16.6. Further reading¶

Godel, Escher, Bach

Read the dialogues “Prelude … Ant Fugue”. All the dialogues in the book might be quite interesting to you.
Watch the rest of the online course on Complexity

In the prerequisites I had you watch some sections of Melanie Michtell’s online course on Complexity. You could watch the rest of the series. At a very minimum watch the sections on genetic algorithms and the game of life.

https://www.youtube.com/playlist?list=PLF0b3ThojznRyDQlitfUTzXEXwLNNE-mI