This is already a more interesting discusion. I cannot comment on Lisp, as I have too little experience with it. When you say python forces you to create interf

This is already a more interesting discusion. I cannot comment on Lisp, as I have too little experience with it. When you say python forces you to create interfaces, I am not sure I understand. For me, programming is mostly about creating interfaces (as the interface part of API), python or not. When I refactor some C code, static typing does not help me that much, as what's difficult in C is lifetime's object (e.g. ref counting in C extensions), things like that. What is true is that it is easy to write code that is impossible to refactor, because it is full of globals, or "stringified API" (e.g. using a dict instead of objects when the set of keys is supposed to be fixed). But I am afraid people writing this kind of code would write bad code in any language, or are at least very inexperienced in the language.