The Origin of Core Values

If a person defines core values as their sacred, foundational values that defines him as what he truly is- how would they come up with those and decide whether these are supposed to be the true values or just what they think are the real values to stick with? I mean, let's examine the various origins of these values.

If one comes up with their own values, does it mean they don't have credibility beyond what that person is - a person without core values? Because he is the one who came up with these values to start with? Right?

And, assuming maybe the subconscious is helping them come up with their own values, while consciously they may not be aware of these, even in that sense, how is their subconscious coming up with values that they're not even aware of? Is there something universal beyond the person's consciousness or their own awareness? Maybe that is something flowing from outside that made them decide what are the core values, even though they're not fully functioning as per the true values that they started defining.

Assuming you want to trust something that you can't comprehend to begin with-Well you trust it.. but how would you know whether your trust is rightly placed?

Yes, you blindly trust something because something must be telling you to do so, isn't it? If that's the case, what's that something? Is it the subconscious itself? Because apparently, the conscious is the one asking this question- and speculating whether the core values defined for yourself are truly the core values or are these just limited by what you can comprehend consciously?