As outlined in the introductory chapter, the work was to deal with the four great orders of men in the Norwegian kingdom: the merchants and their interests; the king and his retainers; the church and the clergy; and the peasantry or husbandmen. In the form in which the _King’s Mirror_ has come down to modern times, however, the first two divisions only are included; not the least fragment of any separate discussion of the clerical profession or of the agricultural classes has been found. It is, therefore, generally believed that the work was not completed beyond the point where the extant manuscripts close. Why the book was left unfinished cannot be known; but it is a plausible conjecture that illness or perhaps death prevented the author, who was apparently an aged man, from completing the task that he had set before him. It is also possible that the ideas expressed in the closing chapters of the work, especially in the last chapter, which deals with the subject of clerical subordination to the secular powers, were so repugnant to the ecclesiastical thought of the time that the authorities of the church discouraged or perhaps found means to prevent the continuation of the work into the third division, where the author had planned to deal with the church and the clergy. In form the _Speculum_ is a dialog between a wise and learned father and his son, in which the larger part of the discussion naturally falls to the former. The son asks questions and suggests problems, which the father promptly answers or solves. In the choice of form there is nothing original: the dialog was frequently used by didactic writers in the middle ages, and it was the natural form to adopt. The title, _Speculum Regale_, is also of a kind that was common in those days.[2] _Specula_ of many sorts were being produced: _Speculum Ecclesiae_, _Speculum Stultorum_, _Speculum Naturale_, and _Speculum Perfectionis_ are some of the titles used for writings of a didactic type. The German _Sachsenspiegel_ is an instance of the title employed for a work in a vulgar idiom. There was also a _Speculum Regum_, or _Mirror of Kings_, and a century later an English ecclesiastic wrote a _Speculum Regis_, but the writer knows of no other work called the _Speculum Regale_. Footnote 2: It is believed that the title came into use in Europe in imitation of Hindu writers who wrote “Mirrors of Princes.” Nansen, _In Northern Mists_, II, 242.