The history of philosophy, as its name implies, represents a union of two
very different disciplines, each of which imposes severe constraints
upon the other. As an exercise in the history of ideas, it demands that
one acquire a ‘period eye’: a thorough understanding of how the
thinkers whom it studies viewed the problems which they sought to
resolve, the conceptual frameworks in which they addressed these
issues, their assumptions and objectives, their blind spots and miscues.
But as an exercise in philosophy, we are engaged in much more than
simply a descriptive task. There is a crucial, critical aspect to our efforts:
we are looking for the cogency as much as the development of an
argument, for its bearing on questions which continue to preoccupy us
as much as the impact which it may have had on the evolution of
philosophical thought