Bion believed that the primitive quality of group psychology corresponded to the most primitive aspects of individual psychology. An immature or more primitive mind thinks only in extremes and in opposites (good/bad, love/hate). A mature mind can understand complexity, can see that people are a mix of good and bad. The world exists in shades of gray; it is not just black and white. In the same way that individuals can regress to more immature modes of thinking, groups too can lose track of shades of gray and jump to extremes.