What is especially intriguing about philosophy, is its sheer ambiguity in the way that it is defined. Philosophy, in all its respects, is the study of the fundamental, underlying principles of a broad range of topics such as political theory, the nature of humans and life, relationship of the mind and body, and reality itself. In essence, philosophy is a process (thank Rocio Galvan) in which one continually uses their wisdom and intuition actively in the world, in an attempt to further understand the nature of themselves, their place or purpose in the universe, and what the universe - or reality, for that matter - actually consists of. "Does it exist?" "Do other minds actually exist?" (I obviously think it does, or I would be a solipsist.)
