294 A Positive Century (1815–1914)that is to say, rejected the liberal idea of rational self- interest as the principal
driving force of social life. Solidarism, with its elitist fl avor, also lacked the
commitment to individual civil liberties and democracy that was such a
striking hallmark of liberalism.
Solidarism’s relation to mainstream positivism was instructive. It was
certainly poles apart from positivism in its disdain for the positivist fi xation
on the in de pen dence and sovereign prerogatives of states. Its adherents pre-
ferred to regard international law as a vehicle for the building of international
consensus and the promotion of ever deeper and more elaborate forms of
interdependence between states. Positivists, in sharp contrast, had far more
limited horizons. Th ey tended to see international law in more limited terms,
as a means of dispute resolution for the inevitable cases in which the rights
and interests of the various in de pen dent states come into collision.
At the same time, however, solidarism was compatible with certain as-
pects of positivism, most notably with the empirical positivists’ focus on
the actual practices of states as the primary source of law. Like the empiri-
cists, the solidarists insisted on seeing the actual relations and practices of
states as the principal source of international law. In this regard, solidarism
shared in the positivist hostility to natural law. Duguit illustrates the close-
ness of this tie. He actually regarded himself as a positivist— of the empiri-
cal stripe, that is, rather than the voluntarist one— and was scornful of
natural law.
Intervention
Of all of the heterodoxical schools of international law, solidarism was the
one that was most forthright in countenancing intervention by states in the
aff airs of one another. Th is is only to be expected, given the core solidarist
principle that the interests of all states are indissoluably bound up with one
another. Th eir community- oriented worldview, by its nature, discounted
the idea that there could be, ultimately, any such thing as a set of state inter-
ests that belong purely to one state alone. On the contrary, the very idea be-
hind solidarism is that the nations of the world, like individuals within soci-
ety, are inevitably one another’s keepers. As Alberdi put it, with disarming
candor, “[w]herever there is community of interests... the right of inter-
vention cannot be abolished.” In par tic u lar, there were two areas in which