I'm not a psychiatrist or even know that much about Jung, but there are some parallels to Moore's concept of Idea Space, so I figured now would be a good time for me to learn, too.
So, as best I understand it, the concept of the psyche developed first with Sigmund Freud, who explored the id. This is what makes you who you are, based upon the things that happened to you. Of course, he was largely working with damaged psyches, so it had a lot to do with trauma and repression.
Jung, however, believed we're made up of more than the id. As verywell.com puts it:
"Jung believed that the human psyche was composed of three components: the ego, the personal unconscious, and the collective unconscious. According to Jung, the ego represents the conscious mind while the personal unconscious contains memories including those that have been suppressed. The collective unconscious is a unique component in that Jung believed that this part of the psyche served as a form of psychological inheritance. It contained all of the knowledge and experiences we share as a species."
Shared knowledge that present themselves as instincts. What are they, and why are they common to all humans? Things like sexual instincts or fear of snakes?
As Moore explained in Supreme, we start in our own psychic backyard and then move on to the everyday consciousness of brand advertising and celebrity. Then we go through our emotions to get to the realm of archetype.
Archetypes were central to Jung, too.
"All the most powerful ideas in history go back to archetypes," Jung explained in his book The Structure of the Psyche.
"This is particularly true of religious ideas, but the central concepts of science, philosophy, and ethics are no exception to this rule. In their present form, they are variants of archetypal ideas created by consciously applying and adapting these ideas to reality. For it is the function of consciousness, not only to recognize and assimilate the external world through the gateway of the senses but to translate into visible reality the world within us," he suggested.
Because people aren't born as blank slates, they need these archetypes to understand how to be human. Jung believed there were four major archetypes, which I'm not going to get into, but are really kind of interesting. You can read more about them here.
Jung's ideas have largely been refuted for modern psychological work, and are often derided for veering into the mystical and pseudoscientific. That said, they seem to work well for Moore's view of Idea Space.
Of course, if any comic writer knows something about archetypes, it's Alan Moore. Moore has spent much of his career as a deconstructionist, getting to the root of the archetypes within the superheroes. As we'll see later when we get to the Kirby issue of Supreme, he'll even refer to different types of superheroes by the creators who invented them. In the pages of Supreme, he'll play with the Superman archetype, the Batman/Shadow archetype, the Wonder Woman archetype and many more.
I think it's telling that he has Supreme find many of these archetypal characters for the Awesome Universe trapped within Idea Space: Professor Night and Twilight, Polyman, Janet Planet. Because that's where the archetypes reside.
But he wasn't content to stop with golden age and later archetypes. As we'll see when we get to Judgment Day, he would start to push the timeline for superhero archetypes back to earlier roots. It's an idea he'd already started to consider with the League of Extraordinary Gentlemen and it's one that would lead to the poster boy for Moore's later ABC line of heroes, namely in Tom Strong. But we'll get there soon enough.