This article presents a classification of conjectures on the text of the New Testament. It
focusses on the types of arguments used by conjectural critics. The argumentation for a
conjecture basically comprises (1) the perception of a problem (or problems) in the
transmitted text and (2) the suggestion of a cause (or causes) for the supposed scribal
change. Type (or types) of perceived problems and of supposed causes are classified,
and illustrated with a range of important conjectures.