Do you program with anonymous values without names independent of their structure, and you can then reason about them equationally? If so, then you have values and probably lambdas to plumb them through the program as they lack their own behavior (you can have lambdas over objects also, but we don't call that functional these days).
Does the language encourage you to think about named entities or does it encourage you to reasoning about values? Of course, not many languages beyond Haskell try to push you to reason about everything as values. And most OOP languages include some form of values these days (if not, we definitely program with immutable objects like points that lack names/identity and might as well be called values).
This is also why OOP is necessarily tied up with state: it doesn't make sense for an immutable container of something to even have a name as it can be only really be identified by its structure.
