The Buddha is your real body, your original mind. This mind has no form or characteristics, no cause or effect, no tendons or bones. It's like space. You can't hold it. It's not the mind of materialists or nihilists. If you don't see your own miraculously aware nature, you'll never find a Buddha, even if you break your body into atoms.
But when you first embark on the Path, your awareness won't be focused. You're likely to see all sorts of strange, dreamlike scenes. But you shouldn't doubt that all such scenes come from your own mind and nowhere else.
If you use your mind to study reality, you won't understand either your mind or reality. If you study reality without using your mind, you'll understand both.
Leaving behind the false, return to the true: make no discriminations between self and others. In contemplation, one's mind should be stable and unmoving, like a wall.
To enter by reason means to realize the essence through instruction and to believe that all living things share the same true nature, which isn't apparent because it's shrouded by sensation and delusion.