There's also the secrets we keep from other people in order to not cause trouble.
For example, you hate this guy at work. You REALLY REALLY ****ing hate this guy at work. Now right now? You can play nice with this person for the sake of not causing trouble at work. Good deal. But in such a reality? There isn't any way you'd be able to hide that.
What of those who hold beliefs that are shunned in their society? Not believing in god in a society that kills non-believers will be difficult if they can probe your mind.
Hell, even when you're talking to yourself you had personal thoughts you'd rather not share with anyone else. To remove that is to remove a right every single human being has.
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