The history of philosophy, like every area of human endeavor, has given rise to criticisms and reservations. Nobody has expressed this more vehemently than Schopenhauer. “To study philosophy, not by reading the actual works of the philosophers, but with the aid of summaries of their doctrines in a history of philosophy, is like having someone else chew one's own food.”

In a general way, Schopenhauer's reservations apply to all history of philosophy, not only to one of its aspects. Nor are they directed against history itself, but specifically against the history of philosophy. The plight of the history of philosophy is worse than that of other fields of history precisely because philosophy itself happens to have the most favorable conditions. In effect, political or economic events are in the realm of the past, while philosophical events remain in the present in the form of manuscripts and books. For this reason political or economic history has a raison d'être: in it a historian reconstructs that which no longer exists, whereas a historian of philosophy merely reproduces what is.