A document in madness, thoughts and remembrance / fitted: A "document" was an instruction, admonition, or warning. The keynote of Ophelia's mad ramblings is at her father's death, and now she brings together the ideas (and flowers of) "thoughts and remembrance." Laertes says that in her madness, Ophelia has delivered a lesson: "thoughts and remembrance" are "fitted," i.e., belong together. We still (C.E. 2015) say that we will always remember and always hold in our thoughts a dearly beloved person who has died. Laertes may also mean that Ophelia is teaching him that he should never forget his father, always remembering who killed his father, and the revenge due.