User blog comment:Zathronas/Analysis by an author: Volume 2 episode 9: Search and Destroy/@comment-23.239.47.154-20141003130704/@comment-66.176.183.83-20141003142048

This is, practically note for note, the MBTI temperament system based on the work of Carl Jung. Yang is the Artisan (SP), Weiss is the Guardian (SJ), Blake is the Idealist (NF). If we go for the full set, that leaves Ruby to be the Rational (NT). Artisans like thrill and mastering whatever the set out to do. They are impulsive and tend to live "in the moment". Guardians are conservatives who put a high value in rank and social status, history, money, and social structure in general. They are driven by duty and prefer security over change. Idealists are those who seek to know themselves and others. They feel an intuitive conenction to people and want to really be true to themselves; in particular, they dislike wearing social "masks" and prefer others to see them "as they are". They look forward towards the future and want universal peace and harmony. Those were, essentially, the answers of Yang, Weiss, and Blake. That leaves the Rationals (my temperament). Rationals value intelligence and reason. They are the great thinkers of the world. They aren't always recognized as such, however, since their ideas are often "ahead of their time" so they may be thought of as "not too bright" and "lacking common sense" for a long time before their genius is recognized. They also lack a strong sense of connection to a particular time period; while Artisans like the present, Guardians like the past, and Idealists like the future, Rationals like intervals that straddle and connect all three periods, though in a close-ended sort of way (guardians and idealists like "open-ended" past and future respectively while rationals tend to put a cut-off to divide the past and future into clear, identifiable segments). Dr. Oobleck is, quite obviously, a Rational given his own answer which is probably why he didn't bother asking Ruby why she wanted to be a Huntress; he already knew.

Check out www.mypersonality.info or www.keirsey.com for more information on MBTI temperament.