Part 2 of Heidegger’s Being and Time devotes considerable effort to building up and establishing the notion of authentic resoluteness. Heidegger’s Dasein may strive to be authentically resolute. I cannot claim to fully understand this concept, but it involves notions such as being-towards-death, maintaining openness to anxiety, and choosing to have a conscience. Somehow, through anxiety and confrontation with death or the Nothing (instead of fleeing in the face of these confrontations, as most people usually do), Dasein becomes able to exist authentically.
C G Jung’s psychology is largely about the process of individuation, which is the mind’s natural growth and progress towards becoming an integrated whole. For Jung, psychological health is largely about resolving obstacles to the individuation process. A big part of this process is the integration of the mind’s unconscious contents (such as the Self) which the conscious contents. This integration seems to not mean that they become a homogenous unity, but rather that they become interwoven and are allowed to influence each other in a natural way.
My hunch, which I cannot argue very convincingly, is that this kind of existential, phenomenological philosophy (Heidegger) and this kind of psychology (Jung) sometimes aim at the same affects, phenomena or states of mind – whichever we choose to call it. Jung makes a big point of differentiating between symbols and concepts. The Self is not a concept but a symbol: it is too large to fully grasp with the conscious mind. Heidegger’s Nothing (or even Being) sometimes looks like this kind of symbol too: something that cannot be grasped by concepts but which is essential for all concepts to be intelligible as such in the first place, a source of intelligibility, the fount from which other notions flow. Turning this around and twisting it a bit, the unconscious can be said to be a kind of nothing, a shadow, and we only have a conscious and definite personality in so far as we also have a shadow to go with it. Our (Jungian) shadow seems to enable our definite character almost in the same way that the Nothing enables beings to stand out “as radically other with respect to the nothing” (What is Metaphysics).
This is mere speculation, but if I am right, then we are led to ask: how is it that Heidegger, who builds his castles (I think) on a kind of language craft and on labyrinthine but highly effective prose, can achieve the same thing that Jung achieves with methods such as dream analysis and active imagination? Could these methods, which seem so different at first, really be aiming at the same goal?