The “Book of the Six Sense Fields” is the fourth of the five books of the Linked Discourses. It is named after the first and longest saṁyutta, which deals with the core Buddhist teaching of the six sense fields. The second saṁyutta on Feelings also deals with a major doctrinal topic. The remaining eight saṁyuttas deal with miscellaneous secondary themes, some organized by subject, others by person.