Disclaimer: I am surely not experienced enough to give a highly informed opinion on the topic. As I mention in the opening I do not think there is a strong dic

Disclaimer: I am surely not experienced enough to give a highly informed opinion on the topic. As I mention in the opening I do not think there is a strong dichotomy between functional and OO programming. I believe historical accident created "Objects vs functions", and by historical accident I mean Java. It is unclear to me why would you not allow to create plain simple functions and force everything in objects. Probably a misunderstanding of "everything is an object". Famously Alan Kay emphasizes "message passing" as the key characteristic of object orientation. Because every discussion about OOP and functional programming eventually ends up talking about State as the main discussion point, I fail to note how a definition of OO based on message passing contrasts the benefits of functional programming around state management. In fact the way I see it is that when we have more units communicating with each other they form a system that should be functionally pure from an external point of view but can be OO in its internal implementation. EDIT: Continuing my train of thought: the problem with OO in it's current common form is that objects often/always leak details about their state. So you have a tuple (state, [actions]) where often using an action is invalid given the tuple's state.