"A man's face as a rule says more, and more interesting things, than his mouth, for it is a compendium of everything his mouth will ever say, in that it is the monogram of all this man's thoughts and aspirations"

In this quote, Schopenhauer explains that a person's face carries more information about them than just what they say with their mouth. He argues that an individual's face is a summary of all their thoughts, beliefs, and dreams. Basically, an individual's facial expressions and features represent their personality and essence.