I first learned BASIC when I was a youngin' too. There's a lot of hyperbole in these "Truths"; I think he's just decrying the poor state of programming languages in those days. I wouldn't take it too literally.

(but who knows? maybe we really are rubbish programmers. Better get started on learning lisp just in case.)

In fact, I'm not sure how many of these are true in academic computer science today. The first one "Programming is one of the most difficult branches of applied mathematics; the poorer mathematicians had better remain pure mathematicians." just sounds like bragging between academic camps.