Very strange book at the time. Factual fact is that in 1970s recursion and self-reference was abhorred. I even remember a lecturer in real-time control, who cle

Very strange book at the time. Factual fact is that in 1970s recursion and self-reference was abhorred. I even remember a lecturer in real-time control, who clearly did not know what a subroutine was. His world view was a state-machine with transition strings between states.