How to write program specifications

A college instructor once gave his students an assignment to “write a four-
function calculator.” One of his students noticed that this assignment was a
very loose specification and decided to have a little fun. The professor didn’t
say what sort of numbers had to be used, so the student created a program
that worked only with Roman numerals (V+ III = VIII). The program came
with a complete user manual—written in Latin.

http://ai.neocities.org/AiSteps.html#AudInput

Drop the [ESCAPE] mechanism down by one tier, into the AudInput module, but do not eliminate or bypass the quite essential SensoryInput module, because another programmer may wish to specialize in implementing some elaborate sensory modality among your SensoryInput stubs. Code the AudInput module initially to deal with ASCII keyboard input. If you are an expert at speech recognition, extrapolate backwards from the storage requirements (space and format) of the acoustic input of real phonemes in your AudInput system, so that the emerging robot Mind may be ready in advance for the switch from hearing by keyboard to hearing by microphone or artificial ear. Anticipate evolution.

http://code.google.com/p/mindforth/wiki/AudInput