I was also struggling with the "big idea is about messaging", the best I can think of is it refers to something similar to "tell, don't ask". Isolation and comm

I was also struggling with the "big idea is about messaging", the best I can think of is it refers to something similar to "tell, don't ask". Isolation and communication is an essential part. While mainstream OO languages focus on higher level concepts like encapsulation, inheirtance, and polymorphism.