# Why The Material World Is Mental

First, there is your mind. You don't really know anything outside
of your mind.

Then I define the material world as things that can appear on your
mind through your senses. Of course those can appear through other
ways like imagination.

Then [Theory] = [Sense]. Even for simply seeing, that depends on
theories of optics (how the light works), anatomy (how your eyes
work), cognitive science (how your mind works), &c.

Think about why you see one clear object when you have two eyes.
It's just that there are innate theories in your mind and you are
so used to them.

And there are things you can't see directly like electrons and
black holes. You just see the results and make theories about them.

Finally, apply Occam's razor and remove any existences that are
not strictly necessary at this point.