So what's wrong with the shell? and what's wrong with Erlang? It's not LISP! - Joe Armstrong

One of the things we’ve forgotten, is the importance of protocols and not describing them accurately.

When I'm writing a program, my approach is to "write a bit" and then "test a bit." I start with a small module with few functions, and then I compile it and test it with a few commands in the shell. Once I'm happy with it, I write a few more functions, compile them, test them, and so on. (page 60)

Object oriented programming asked you to put things into categories, into classes. Concurrency oriented programming asks you to identify the concurrency and the problem. The concurrence in the problem is a property of the real world. If you are doing real world modeling you can see it, you can smell it, you can eat it