What is the difference between a paradox and an oxymoron?

An oxymoron is only a few Words that appear to contradict one another-think Romeo and Juliet-"cold fire" or "happy grief" are examples. Although it suggests a paradox, it is easily confined to its sentence. A paradox is a larger version of an oxymoron, usually a statement/sentence versus two to three Words: "My only love sprung from my only hate" (also R&J). The key is that they shock the reader and make him/her pause to think because the Words/phrases don't seem to make much sense together, but when examined more closely they reveal a truth. The relationship between oxymoron and paradox is similar to the relationship between metaphor (a few Words) and extended metaphor (carries through a paragraph/poem/entire work in detail).