We did it twenty-five to thirty percent for the sake of doing it because it was something we could do and do well, and sixty percent for the sake of having something which was in its metaphorical way alive, our offspring, which would do things on its own when we were finished. That's the great thing about programming, the magical appeal it has ... Once you fix a behavioral problem [a computer or program] has, it's fixed forever, and it is exactly an image of what you meant.