Realism and World Politics

Wendt has reduced scientific realism (a prominent species of philosophical
realism) to three propositions:

1 the world is independent of the mind and language of individual observers;
2 mature scientific theories typically refer to this world,
3 even when it is not directly observable.^55

Practically speaking, most us are empirical realists most of the time; proposition 1
summarizes what we think as we get along in the world.^56 Positivists routinely accept
2 along with proposition 1. They resist proposition 3 on methodological grounds,
although they (have little choice but to) tolerate proposed nonobservables if they
have consistently observable implications.^57 They would not criticize Waltz, as I
have, for moving from structural causes to institutional effects, if he drew out
observable implications with appropriate care. Yet they would join philosoph-
ical realists in rejecting Waltz’s enterprise insofar as it does not comport with propo-
sition 2.
Compare these remarks, one from a positivist willing to countenance unobser-
vables with observable effects (Robert Keohane) and the other more recently from
a philosophical realist (Milja Kurki). Keohane wrote:

Although Waltz is content to make theoretical assumptions about units that

deviate sharply from their known patterns of behavior, this is not, paceMilton

Friedman (1953), a universally accepted practice in the natural or social

sciences.^58

Kurki wrote:

While trying to avoid seeing the international system as logically ‘necessitating’

effects in the ‘when A, then B’ manner, Waltz finds it hard to resist deducing

logical effects from the system. Arguably, this is because the microeconomic

model his theory is based on works on the basis of a ‘closed system’ view of

the social world.^59

Both comments direct attention to Waltz’s reliance on microeconomic theory in
developing his structural theory of international politics, and more especially to these
claims of Waltz’s:

Economic units and economic markets are concepts, not descriptive realities

or concrete entities. This must be emphasized since the early eighteenth

century to the present, from the sociologist Auguste Comte to the psychologist

George Katona, economic theory has been faulted because its assumptions fail

to correspond to realities. Unrealistically, economic theorists conceive of an

economy operating in isolation from its society and polity. Unrealistically,

economists assume the economic world is the whole of the world.^60

98 Structure? What structure?