Doubling rules [cellular automata]
Forms of [engineered] artifacts
Higher perception and analysis
History [of extraterrestrial life]
[Ideas of] meaning in programs
[Meaning in] molecular biology
Messages to send [to extraterrestrials]
Minimal cellular automata for sequences
Other examples [of minimal systems]
Possible purposes [for systems]
Practical arguments [about exterrestrials]
Properties [of doubling rules]
[Rules implementing] other functions
Science fiction [and extraterrestrials]