  The Exigit ordo is also known as the Tractatus universalis (Universal Treatise). The latter title is actually a misreading of the first two words of the treatise, “tractatus utilis” (useful treatise). It has been preserved in a single manuscript copy, which, like the Giles letter, breaks off in mid-sentence. It is divided into two prologues, two treatises, and several chapters, which, unfortunately, the scribe has placed in the wrong order. The Latin edition and English translation both preserve the order of the medieval manuscript without correction.