The real self is utterly different; not only utterly different from your false self, it is diametrically opposite to it. You cannot have any idea of the real self through the unreal self. The unreal has to cease for the real to be. The unreal has to go absolutely.
What idea can you have of light if you know only darkness? Whatsoever you will think of light will remain a form of darkness. You know darkness.
That's why Buddha has chosen a negative way. He does not talk about the real self, atma, soul, atta. He talks about anatta, no-self, anatma, absence of self. He negates the whole idea of the self because the idea of the self will carry, will remain continuous with, your false idea of the self.