Clojure does not remotely hold that "mutable state is wrong." That precisely why it provides several different ways to access mutable state from concurrency pri

Clojure does not remotely hold that "mutable state is wrong." That precisely why it provides several different ways to access mutable state from concurrency primitives down to mutable arrays. Rich's philosophy on this is "mutable code isn't needed most of the time." It's a very different argument. As for (2), if by "real world problems" you mean "commonly occurring, trivial, day to day problems", then yes, I also solve "real world problems" every day with clojure.