Of Spiders and Bees 197Th is voluntary law was closely related to the natural law of nations in being
“derived from the same source and based upon the same principles.”
One advantage that the voluntary law had over the necessary law was in
being “of more certain and easy application.” Th e most important diff er-
ence, though, was that the necessary law of nations was binding chiefl y on
the consciences of sovereigns, whereas the voluntary law controlled their
external actions. Th is distinction went far toward relegating the whole of
natural law to the realm of morality, while leaving the voluntary law as the
unchallenged ruler in the sphere of strict legal relations.
Another of Wolff ’s ideas that was put into wide circulation by his emi-
nently readable follower was the principle of the legal equality of states. It
will be recalled that Pufendorf had been an earlier articulator of this the-
sis. But it was Vattel’s exposition that made the greatest impression on fu-
ture readers and writers. In asserting the legal equality of these moral per-
sons with one another, Vattel employed a winsome analogy in pointing out
that a “dwarf is as much a man as a giant is”— and that, by the same token,
“a small Republic is no less a sovereign State than the most powerful king-
dom.” A common later form of this viewpoint would be the pronounce-
ment that Rus sia and Geneva were equals in the eyes of international law,
notwithstanding the mammoth disparity in size and power between them.
Vattel has sometimes been understood— or rather misunderstood— as a
radical champion of state sovereignty. But here, as in the case of Pufendorf,
caution is called for. What Vattel was insisting on was the legal equality of
states with one another and the principle of nonintervention by states in the
aff airs of one another. State sovereignty was not unlimited, so long as the
canopy of natural law overlay international aff airs in general, which Vattel
clearly held to be so.
In one noteworthy respect, Vattel parted company with Wolff. He rejected
his pre de ces sor’s idea of a global supreme state, dismissing it as a “fi ction”
that was “neither reasonable nor well enough established ” to ser ve as a source
of binding rules of law. In addition, and more importantly, Vattel made
some innovations of his own, most notably in the areas of war and neutrality.
Regarding neutrality, he provided the fi rst explicit explanation for the right
of belligerents to infringe the freedoms of neutrals by such means as captur-
ing contraband of war (i.e., goods that are connected with war, such as arms
and ammunition). He justifi ed this action in terms of what would later be