The reality is our brain is vast and full of a myriad of random thoughts and impulses, some dark, but our executive function is the switchboard that chooses what we think and what we disregard. That is the reflection of who we are.
We have this fallacy wherein we think the deepest thoughts are the most real; that people who have private thoughts but do not act on them are hiding' their true self; but nothing is less true. It is who we choose to be and what we choose not to be and not to give weight to that is the best reflection of our self.