When I was a high school student, I read “Artificial Life” by Stephen Levy and got really into alife. The book had snapshots of a daughter of Codd’s CA, Langston’s loops, on its book sleeve. I was able to back up some of the rules and then deduce what the others were to repro this CA. I still chase that feeling I got from doing this.
How does this differ from Langton’s Loops? The two wiki articles don’t seem to reference each other.
Langton reduced the amount of rules for their construction by removing the ability for Universal Computation but still having self reproduction.