From the three you then use one
To make ten ones…
(And you know why four plus minus one
Plus ten is fourteen minus one?
‘Cause addition is commutative, right.)
And so you have thirteen tens,
And you take away seven,
And that leaves five…
Well, six actually.
But the idea is the important thing.
Tom Lehrer, “New Math”
What can we take from this introduction? Well, our author can’t be bothered to define basic arithmetic properly. What he really wants to say is, roughly, Peano arithmetic, with 0 removed. But my guess is that he has no idea what Peano arithmetic actually is, so he handwaves. The real question is, why did he bother to include this at all?
My own experience is primarily with physics crackpots and creationists, but there are obviously math cranks out there, too.