I'm sure the author's claim about mutual exclusivity will be disproven by some of the absolute madmen posting here, but I'm definitely one more point in favor of his hypothesis. Even though Lisp holds a special place in my heart as the first language I really learned, I always found that macros beyond the standard stuff like let and cond weren't worth the trouble and ultimately made my code harder to read. Monads, while also a significant abstraction, simplify the logic of the program (and its syntax) far more effectively imo. I'm less timid reading somebody else's Haskell code, while I'm terrified of anything I wrote myself in Lisp a few months prior.