Good one! and (I believe) quite correct!

It's both, most probably. We know experience exists, beyond that it's really impossible to say for certain, but I'm still of the opinion that mountains are mountains and rivers are rivers.

A fervent wish seconded heartily by yours truly. May all our heads remain in the real world for there is none other and in reality none better!

Thank you! Very wise!

Experience can only be in our heads, and that is what we base all our speculation on...experience. Although we have no reason to doubt our senses, we have little reason even to doubt our interpretation, as far as it goes...as long as we are operating in a Newtonian world, we will be fine, things may not always go our way, but we are hoodwinked into thinking there is some knower behind the knowing, or some actor behind the action, when this whole presupposition upon which most of us build our lives, is completely open to criticism. For one thing, how far does this thing go back. If there is a controller controlling me, who controls him?? and so forth and so forth. So that's one of our dearest theories down the tubes! That's why I favor poetry as a way of expressing all that we experience! Because it has no limits and does not even aim at what is factual, bu only aims at the truth, that oh so enigmatic and ephemeral of subjects...

You're right

Doesn't all experience in a sense take place in your head, that is inside your brain?

Well there does appear to be in a way, two worlds, one real world out there, and our perception of the world out there, as well as how we think about it, focus on various aspects of it, philosophize about it; but in a very real sense that is going on inside our skulls; nevertheless, belief in this so-called outer world is rampant and it appears endemic to the race. One is certainly inclined toward belief in an outside world, because one seems to be running into it quite frequently in such away as to remove any doubt of it's existence; however, it is by its very nature, beyond proof! It is simply taken as a given, like one's own existence, and never seriously questioned. This is for the most part as it should be, for we seem incapable of acting any other way, because even when we take up the opposite viewpoint, there seems to be no material difference in how we comport ourselves, entirely as though the outer world existed! And why not! Why not indeed! And how indeed can one do other?

@MajesticHero
I was refering this immediate moment, not generalising., but what you say is true !