Ok, what I meant by that was that everything that is 'defined' and 'solidified' (I don't think I know the right word to describe it) is a function in that you can't define variables of type, they're all something that a function returns, and have a more etherial quality. Yeah, I really don't have the words for what I think I'm trying to say, and I don't actually know that either, I'm just going by what people have told me and what I have read of haskell. I'm by no means even familiar with haskell at this stage, so whatever I say about haskell is conjecture from the perspective of a novice in an attempt to describe things to the extent that other novices can have a quick entry path to live-coding (which is the aim here rather than into FP/haskell)

Really, that myth is common? If so it explains why people seem to be afraid of Haskell: they think it has no numbers, characters, strings, lists, arrays, etc.

Someone who believes the myth and is aware of Church encodings probably thinks everything is Church encoded in Haskell. Someone who believes the myth and is not aware of Church encodings will likely have no mental image to associate to Haskell, and feel it is truly alien.

It may be wrong, but is it, perhaps, a harmless and useful way to understand Haskell?

(I have a friend who always tries to show me examples of neat stuff he's done in Haskell and I can never wrap my brain about it)

It's not useful at all, it makes Haskell sound bizarre. Haskell is much more of an ordinary programming language than this would suggest: like ordinary languages it has functions but also numbers, strings, list, arrays, etc.

When discussing technical matters, anything that isn't technically correct should be accompanied by a disclaimer.

I usually like to say "just about", "informally" or "while there are some exceptions, it can be helpful to think about it as if..."