Medieval Geopolitics: The Evolution of Positive Law

By Andrew Latham

In my last column, I summarized the content of Quanto personam issued by Innocent III, which espoused the absolute authority of the Pope. I argued that this document quickly became the basis for a theory, not only of spiritual, but also of secular absolutism. In this column I further develop this line of argument by tracing the next stage in the evolution of the ideas first laid out Innocent’s influential decretal, focusing in particular on the writings of the canonist Laurentius Hispanus.

The canonists of Bologna developed the ideas that Innocent had introduced in Quanto personam in a number of ways. Laurentius Hispanus, in one of the decretal’s earliest glosses, initiated this process by taking up the question of the limits of papal plenitudo potestatis. The canon lawyers of the twelfth century, of course, had constructed a doctrine of papal primacy that emphasized the pope’s supreme authority to command, legislate and judge within the institutional Church. Significantly, however, this doctrine did not construe papal supreme authority as being unconstrained or absolute. Popes, for example, were not permitted to change the unwritten constitution of the Church, the status ecclesiae. Nor were they permitted to alienate the rights attached to the papal office.


Nor, significantly, were they permitted to legislate arbitrarily. The pope’s legislative authority was limited by the principle that, in order to be valid, any laws he promulgated had to correspond to both justice and reason. Twelfth-century canonists like Huguccio simply could not imagine that a law could be legally binding unless it was both just and reasonable – that is, in accord with natural and divine law as apprehended by human reason or revealed in scripture.  Man-made laws had to reflect the higher norms of natural and divine law, otherwise they were considered not to be laws at all.

It was this last limitation that Laurentius was to reconstruct, in the process inadvertently laying the foundations for the later development of the idea of both positive law and absolute power.  As Kenneth Pennington has argued, underpinning the conception of papal authority prevailing before Laurentius’ time was a tension between two understandings of princely power. On the one hand, there was a current of Roman law thinking represented by the claims such as ‘what pleases the prince has force of law’ and ‘the prince is not bound by law’ that viewed the prince as the source of the law and his power as therefore unlimited. On the other hand, there was the view – expressed in another current of Roman law, as well as in Germanic law and feudal custom – that while the prince may be the source of the law, he was not free to enact any law he pleased.  Law, to be valid, had to be just and reasonable. By the time of Huguccio, this tension had been resolved in canonist thought by arguing that the will of the pope had force of law because his will was informed by reason. The ultimate source of the law, they assumed, was thus reason, not simply the prince’s unconstrained will.

Laurentius’ evolutionary move was to gloss Quanto personam in such a way as to invert this formula.  Motivated by a desire to enhance papal legislative authority to “overcome the vast mass of worldly and often corrupt customs that dominated the life of the church” he asserted that no longer was the pope’s will informed by reason; it was reason.  As Laurentius put it,


[The pope] is said to have a divine will…. O, how great is the power of the prince; he changes the nature of things by applying the essences of one thing to another…. He can make iniquity from justice by correcting any canon or law, for in these things his will is held to be reason.

The consequences of Laurentius’ inversion of the prevailing canonist formula were twofold. First, he decisively established that one source of the law was the prince’s will. In claiming that the pope’s will is held to be reason, (Pro ratione voluntas) Laurentius was arguing that in certain circumstances the pope’s “divine will” could substitute for reason as the font of legitimate law. Normally, positive law (ius positivum) was grounded in reason. Occasionally, however, a law promulgated by the prince was not consonant with reason. On these occasions, the prince’s will substituted for reason as the underlying source of that law’s validity.

Second, Laurentius’ inversion introduced a new way of thinking about the content of the law. Whereas the prevailing view at the time was that positive law, to be valid, had to reflect natural or divine law, Laurentius asserted that there was no necessary correlation between the two. If the pope could change what was previously held to be just into an iniquity, then obviously positive law was not necessarily an expression of unchanging natural or divine law. Indeed, Laurentius’ argument strongly implied that positive law was nothing more than a human ordinance legislated by a competent authority.  It also implied that that competent authority had the power to enact laws that were neither just nor reasonable in the traditional sense. None of this is to suggest, of course, that Laurentius understood the pope’s legislative power to be completely unbridled. The concluding words of the passage quoted above are, ‘He is held, nevertheless, to shape his power to the public good.’


Moreover, the goal of the canonists at this time was to enhance the pope’s authority to repeal old laws and enact new ones – not to challenge the “permanent truths” of Scripture or to set the pope above them.  Rather, it is to make the argument that Laurentius’s gloss on Quanto personam identified the pope as the ultimate wellspring of legislative authority within the Church and thus conferred on him unprecedented freedom when enacting positive law for the good of the Church.

Andrew Latham is a professor of political science at Macalester College in Saint Paul, Minnesota. He is the author, most recently, of The Idea of Sovereignty At the Turn of the 14th Century. You can visit Andrew’s website at or follow Andrew on Twitter @aalatham 

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Top Image: Image of Pope Innocent III, British Library


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