310 A Positive Century (1815–1914)In personal terms, the two men were rather diff erent. Martens was a some-
what haughty and self- important fi gure (scorned by one fellow conference
participant as having “an explosive lack of tact”). Renault, in contrast, was
the incarnation of modesty, self- eff acement, and generosity. If he was never
the author of a magisterial treatise, as Martens was, he nonetheless stands
out as the great international-law teacher of the period. Concurrently with
his appointment at the University of Paris, he taught at the School of Po liti-
cal Sciences and at two of the military schools. Over the course of his forty-
four year teaching career, he is said to have directed an astonishing total of
252 doctoral theses and to have taught a number of persons who achieved
later eminence (including Álvarez, who regarded him as a major inspiration
behind his thinking). If any one deserves the title of schoolmaster of
nineteenth- century international law, it is he.Abroad in the World
It will be recalled that one of the most important features of international law,
to the mainstream positivists, was its fundamentally contractual character—
it was a law between nations. Th at immediately implied that international
law could not be truly worldwide in scope— a point that writers in the natu-
ralist school of the seventeenth and eigh teenth centuries, such as Cocceji,
had made. Like any man- made system, international law must inevitably
bear traces of the historical context in which it was formed. Th at meant,
specifi cally, that international law must be acknowledged to be, fi rst and
foremost, a product of E u r o p e a n civilization.
In this vital respect, the contrast with the natural-law outlook could hardly
be starker. Natural law was a thoroughly cosmopolitan system, embracing all
cultures, religions, and races and regarding the whole of humankind as ulti-
mately a single family (and ideally a harmonious one at that). In this vision,
there was no room for according a privileged status to the Eu ro pe an states
and their off shoots. But the position was far otherwise on the positivist view.
Th e elaborate system of customary and treaty law that built up over time, and
especially throughout the nineteenth century, was the product of Eu ro pe an
eff ort. And since international law, by its nature, was seen as a contractual
system, it inevitably followed that the only states that were full members of