International Relations. A self-Study Guide to Theory

Assumptions of neorealist theory 
•
States as unitary actors (“units” of the international system) and the most 
important actors in international politics
•
Power as the most important political means used by actors
•
Hierarchy of actor’s (state) goals: „high politics“ (security) and „low 
politics“ (all other issue areas) 
•
Anarchy of the international system 
•
Actors (the “units”/states) motivated by self-interest because of the secu-
rity dilemma 
Step 3: 
The neorealist explanation of international politics 
3.1. Level of analysis 
Having discussed the basic assumptions, we will now take a closer look at the 
explanation a neorealist theory offers for the outcomes of international poli-
tics. In the fourth unit of the first part, we defined outcomes of international 
politics as the patterns of interaction such as conflict, war, peace and coop-
eration. These are what have to be explained by a theory of international poli-
tics (the explanandum). The explanans is what explains these outcomes. A 
central question is where the explanans is “located”, i.e. where to focus our 
study in terms of levels of analysis.
For Waltz, statements about war and the conditions for peace in interna-
tional politics are made according to the level at which the causes are located 
– whether they originate with man, the state or the state system (Waltz 1959). 
He shows a clear preference for explaining international politics at the sys-
temic level. In fact, for Waltz, a theory of international politics is a system-
level theory. He supports his preference for the systemic level by drawing a 
sharp line between reductionist and systemic theories. Please be aware that 

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the term “reductionist” as used by Waltz should not be confused with “reduc-
tionism” as introduced in Part 1 from a philosophy of science perspective. 
Theories that concentrate causes at the individual or state level are reduction-
ist. According to Waltz, we have to distinguish between a theory of interna-
tional politics (systemic) and a theory of foreign policy (reductionist). Reduc-
tionist theories understand international politics in its entirety by knowing the 
attributes and the interactions of its parts (the states), either through explana-
tions of group behavior resulting from the psychological study of the group’s 
members or through efforts to explain international politics by studying state 
bureaucracies (Waltz 1979: 18). Reductionist theories explain international 
outcomes through “elements” or “combinations of elements” located at the na-
tional or subnational level; internal forces produce external outcomes. For 
Waltz, reductionist theories do not provide adequate explanations for outcomes 
in international politics. His “project” is the construction of a non-reductionist, 
system level theory. In this regard, Waltz builds on criticism of the dominating 
studies in international politics in the 1950s, 1960s and 1970s.