This series is composed of roughly 1,173 dictabelts that contain the oration of Wilfrid Sellars. Most of the dictabelts have labels written on them in chalk pencil. These dictabelts are usually grouped in nested sets and labeled with the same title and a sequential number. The 865 labeled dictabelts fall into several categories: manuscripts, correspondence, miscellaneous, dated and untitled. The dictabelts classified as manuscripts seem to be pre-cursors to articles and lectures, both published and unpublished. The correspondence appears to be pre-cursors to letters Sellars sent to colleagues. The dated and untitled category houses dictabelts that currently cannot be identified. For example, some have only a date label done in chalk, while others have no label whatsoever. The dictabelts preserved all show signs of having been used by Sellars. However, only a small number have been played by the archivists, confirming that at the dictabelts are still in usable condition.