The 4 Characters Personality.How to understand each other (Introvert/Extrovert/Stable/Neurotic). We are by nature people who are designed not to share. Although many have trained themselves and grew up in an environment that has shown them compassion, understanding, and love; many may not understand the advantages and theory of personalities and how it relates to ourselves and why people are compassionate, moody, carefree, leaders, or passionate.