I think it's unfortunate you haven't even looked at Clojure. If you did, it's possible both languages could benefit. While I am a fan of the JVM, one downside

I think it's unfortunate you haven't even looked at Clojure. If you did, it's possible both languages could benefit. While I am a fan of the JVM, one downside of the language is that compromises were needed to work nicely on the JVM. Besides that, Clojure has many features that make programming in it great for experimentation (and large-scale), and I don't see those features in Arc. If Arc had immutability, threading, STM concurrency, lazy functions, and literal data structures, but without the JVM compromises and with the 100-year goal, it might be more interesting to me and others. I looked at Arc when it first came out, but the homepage still doesn't spell out what makes it worthwhile other than "brief and malleable".