>Smalltalk has the cleanest, purest implementation of object-oriented concepts; not even Java, Ruby, nor CLOS can lay claim to that.
I'll take "powerful" versus "cleanest and purest" any day, thank you very much. Sorry but i'm staying with CLOS whenever i want to do object-oriented programming without feeling limited.
The author is on a pro-Smalltalk crusade (which I find just fine, Smalltalk is a great lang, and in a perfect world, it would be as popular as Javascript is today), but does so at the expense of constantly deriding Clojure, Common Lisp and Racket, which I find silly.