This principle and method of examining objects through historical connections and changes is called historicism.

Historical philosophy refers to a theory.

General history books are just history, but historical philosophy is a history written by philosophical methods, that is, "social history written by philosophical methods". Therefore, books on history and philosophy are both historical books and philosophical books.

It should be noted that' historical philosophy' and' philosophical history' are also different.

The history of philosophy is the history of philosophy, which is an independent history of philosophical development.

But' historical philosophy' is the history of the whole society (only written in a philosophical way).