"I know only two words of American slang, 'swell' and 'lousy'. I think 'swell' is lousy, but 'lousy' is swell"

This quote by J. B. Priestley is a humorous method of revealing his viewpoint on the 2 words of American slang he knows. He is indicating that he does not believe highly of the word 'swell', as he thinks it is 'lousy'. However, he does believe extremely of the word 'lousy', as he believes it is 'swell'. This quote is a smart way of expressing his viewpoint on the two words, as he is using the words to explain each other. He is also making a joke out of the words, as he is using them in a way that is opposite to their intended meaning. This quote is an amusing method of expressing his viewpoint on the 2 words of American slang he knows, and it is a creative method of making a joke out of the words.