Lets say that you would like to tell your mother every day that you're a nice guy (authentically)(or use any other real life social scenario where it benefits to have a different position from your own)...eventually you yourself will start believing that you're a nice guy (or whatever that position is).
You have two realities, which both have to be REAL (they have to be authentically believed in the moment), one is a lie, it is for your mother, and a different one, the truth, for yourself.
Both have to be authentic, therefore you must believe in both (in their appropriate contexts). But one is for social contexts and the other one is for yourself. It's VERY easy to get lost in the social context one, because it's the one thats repeated OVER AND OVER.
So the one that's repeated more often starts to crowd out the one for yourself. Eventually you forget the inner one and start believing in your own bullshit. Getting lost in the sauce.
Not really, I want to retain a clear image of multiple of my realities in my mind for different contexts.
It's also necessary to retain multiple external perceptions, but I've never had a problem with that.
What's hard is believing something is both blue&red in one mind in various contexts. Especially, if one of them (lets say blue) is used constantly by your public identity in every social setting, but you also want to remember that it's red.
A 100% truth-teller is like a clear mirror, any information in their possession can be easily accessed by friends and enemies alike. Making them completely untrustworthy to anyone that wouldn't like all the information they share to become 100% public knowledge.