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In Europ, a person's "self" consists of three parts: the conscious self, the inner self, and the social self.
Intelligence is your conscious self: your ability to evaluate, analyze and learn. Of the three selves, your intelligence determines how well you interact with your physical environment.
Wisdom is your inner self: your understanding of who you are, your ability to resist temptation, your awareness of magic which attempts to influence you. This has secondary effects as well, because your inner self possesses a greater wellspring of knowledge than your conscious self, and a person with great wisdom can tap that for insights and intuitions.
Charisma is your social self: your connection to other people, your ability to influence them, your awareness of their mood and character. A strong charisma means that your connection to others is strong enough that they tend to trust you more readily, follow your lead in more things, or even sublimate their own personality beneath yours. To some extent, this outward connection and exertion even allows you to influence events.