The Reality of the Ghost under the Mattress
The fact that a shadow frightens you proves the existence of your heart, not the existence of the ghost.
We must notice that the human mind itself is reality. What is real is not only what you see, but the mechanism of seeing itself. Thoughts are real events. Beliefs are real neural processes. Religions are real cultural phenomena. An idea of God is a real state of a human brain.
But the rookie error is to conclude that because the belief is real, the object of the belief is therefore real in the same sense. To use a simple example, fear of a monster under the bed is a real fear. The increased heart rate is real. The neural activity is real. The behavior of checking under the bed is real. None of that tells us whether the monster exists.
The belief belongs to reality as a psychological phenomenon. Its referent may or may not belong to reality as an independent phenomenon. That is why there are really three questions rather than two.
The first is Is the belief psychologically effective?
The second is Does the belief correspond to something outside the mind?
The third is Does the belief remain open to correction by reality?
These questions can have different answers if you are in reality or asleep.
