Economics. These criticisms of Marxist theory were
based mainly on empirical data, and their validity
depended in good part on the time scale to which the
theory was related. But Bernstein also tackled what
many regarded as the central doctrine of Marxist eco
nomics—the labor theory of value and surplus value.
Bernstein's discussion of this theory did little more than
hint at a synthesis of the Marxist and increasingly
accepted marginalist versions of value theory, and he
concluded by treating the concept of value more as
an abstract tool of analysis than a fact of the real world.
Surplus value, however, he regarded as “a fact demon-
strated in experience”; while denying that the rate of
exploitation was directly related to the rate of surplus
value, Bernstein emphasized that exploitation was in-
deed a feature of capitalism (ibid., pp. 28-40).
