This book has endeavored to answer Stephan Kuttner's question: “Was it [the Decretum] drafted and completed in one grandiose thrust, or did the original version go through successive redactions?” I hope to have proved that the latter is true. Kuttner followed his question up with another: “And if the latter, was it Gratian himself, or Gratian with his disciples, or an early generation of canonists after him, who completed the final recension which from the mid-twelfth century on was used in the schools and in adjudging cases?”

Kuttner's second question has become even more pertinent with the discovery that two distinct recensions of Gratian's Decretum are preserved. Did the two versions have the same author? There is no external evidence to throw light on the issue; in fact, nothing at all is known with certainty about Gratian, except that he wrote at least one recension of the Decretum. Under these circumstances, almost the only available evidence is the style and content of the texts themselves. Internal evidence of this kind is, however, seldom conclusive; many long-standing debates about the authorship of texts have arisen when the evidence is of this kind, as with fragments of the ancient poet Gallus, the Pauline epistles, the Rule of St. Benedict, and several Shakespearean plays. It may ultimately turn out to be impossible to determine with certainty whether or not the same man wrote the two recensions of the Decretum.