Chinese artists often express their philosophies using calligraphy. Which is the best definition of philosophy?

A. a complex idea
B. a religion
C. a way of practicing creativity
D. a system of guiding principles

D. A system of guiding principles. Philosophy refers to the study of the fundamental nature of knowledge, reality, and existence. It is a way of thinking about the world and understanding our place in it, which involves the examination and exploration of concepts such as ethics, logic, and metaphysics.