writing on rhetoric and modes of appeal

in a concise blog post, explain in your own words the general ideas contained in rhetoric and aristotle's modes of appeal. then explain how you see them functioning within the various spheres of the graphic design world. this should only be one or two paragraphs.

some questions to get you started. no need to follow these; they're just starting points

• how doe the modes of appeal function and how are they different? 
• are they typically used for specific content types or in specific media? ex: pathos is always used in fashion, etc
• do you see specific uses of rhetoric cropping up in specific cultures/subjects/media? ex: metaphor in car ads, personification for home cleaning products
• what makes for the most effective examples of rhetoric? is it vivid imagery? unique layout? highly focused content? minimal message?