The document discusses musical blind spots, which are genres of music that people do not enjoy even though they are widely regarded as influential. The author's biggest blind spot is their aversion to the Beach Boys album Pet Sounds, which they understand is influential but cannot enjoy listening to. The document encourages readers to identify their own musical blind spots and consider genres they may not typically listen to, such as rap, rock, jazz, or pop music. It provides brief overviews of the histories of these genres and notes that everyone has musical preferences that could be considered blind spots.