I'm going through a Persona's Quirks in Mythus and it has occurred to me that what Trait a Quirk falls under isn't exactly what somebody else thought they did. In particular, in GURPS what somebody decided was a Mental or Spiritual Quirk is actually best applied to a different Trait. For the most part what somebody decided was a Mental Quirk works better as a Spiritual one.
Now in Mythus the Mental Trait is made up of two Categories, Mnemonic and Reasoning. That is, memory and cognition. The Spiritual Trait is composed of the Metaphysical and Psychic Categories. Which is to say, one's understanding and knowledge of reality and how connected he is to reality. That is, how grounded he is and how well he understands the world around him. So what is a Mental Quirk in GURPS is a Spiritual Quirk in Mythus. At least that's how I see it.
And this means that I need to rearrange matters. And it seemed so simple.