The article presents the usual dichotomy: static typing helps with correctness but makes programs harder to write--your language is less expressive. I used to b

The article presents the usual dichotomy: static typing helps with correctness but makes programs harder to write--your language is less expressive. I used to believe this too. Now I think this is a false dichotomy. In this rare instance, you can have your cake and eat it too. I used to mostly use dynamically types languages: Python, JavaScript, Perl, Scheme. I also used Java and C++, but did not think they were worth the sacrifice in productivity. However, recently, I've been using Haskell. I really like it for reasons of correctness; however, I was also pleasantly surprised to find I was more productive in Haskell than in any dynamically typed language--even Racket (a Scheme variant). There is one very simple feature in Haskell that makes it concretely more expressive than a dynamically typed language: typeclasses. You can have values polymorphic on their return type, which makes things like overloaded string and numeric literals possible. However, it's more than this. Types help me think about my problem and constrain the solution space. I often overcome logical problems by figuring out how the yours should match. There are a bunch of factors like that, but they really are a matter of preference. Typeclasses aren't: you simply can't do certain things as easily without them. QuickCheck is another great example; it's far easier to use in Haskell than in, say, Erlang. For my most recent project, I was able to use 18-bit words very easily. Moreover, it would be trivial to make my code generic over the exact type of number used! I'm thinking of passing in probability distributions instead of numbers per se. That's also easy thanks to typeclasses. In summary: I've found static typing can be more expressive, partly out of preference but largely thanks to typeclasses. Somebody once asked me what I thought the most important feature of Haskell was. I said typeclasses, and I still stand by that.