I stopped reading at exactly this line. With it he established that he's merely speculating, and quite frankly I'd rather live with my own speculations than his.
Good point. Added Haskell
Lisp, Scheme, Erlang are functional languages, but they are not pure functional languages.
Also, Scheme is Lisp.
I was referring to Common Lisp. Corrected it.
Common Lisp has more in common with Python and Ruby than Haskell. Perhaps you should study some of these languages before encouraging other people to.
Arguably, so does Scheme. My impression of Ruby is that it's sort of a bastard of Perl and Scheme.
I'm a heavy Common Lisp user, but I'm only casually familiar with Scheme, so I opted to leave deconstruction of that aspect to others--such as yourself!
More like Perl and SmallTalk.
Scheme is a bit more biased in favor of functional techniques though. Recursion (in the vast majority of cases CLers will just use (loop) instead of recursing), continuations...
Edit: I meant to say functional not pure functional. Blog post changed.
He's making the distinction between saying a language is "functional" versus "pure functional." It is not correct to classify Lisp and Erlang as pure functional languages, because they both include support for imperative style programming.