I think the exact opposite: the only good judges of syntax are people who understand the semantics deeply enough to understand whether the syntax accurately ref

I think the exact opposite: the only good judges of syntax are people who understand the semantics deeply enough to understand whether the syntax accurately reflects them. It's all well and good to say that people should be able to bounce around between languages within a paradigm. A Rubyist should be able to read Python, Perl, and PHP, sure. A Java programmer should be able to read C++ and C#. Claiming that people should be able to read any programming language, though, means that languages aren't allowed to explore significantly different semantics. A JavaScript programmer isn't going to be able to pick up something written in Prolog or Forth and quickly understand exactly what's going on, and that's as it should be. The whole point of having multiple paradigms is that they can express different ideas and ways of approaching problems. So, I agree that an SML or OCaml programmer should be able to "get into the groove" with Haskell quickly. In my experience, this is usually the case.