The word philosophy comes from two Greek words meaning "love of wisdom." In this sense philosophy is an immensely practical discipline which seeks to inform those in search of "the good life." But the wisdom that philosophers love extends beyond such stereotypical questions as the meaning of life. Philosophers examine issues that are foundational to the rest of rational inquiry: What kinds of things are there in the world? What is knowledge, and how do you know when you have it? How ought people to live in relation to one another? What is the proper role of government? What are worldviews and how do they affect our appraisal of reality? What is good reasoning, and when ought we to be persuaded by others?
The methods of philosophical inquiry, especially logic and critical analysis, provide intellectual tools to engage issues across different disciplines. The resulting second-order inquiries have come to be called "philosophy of" science, education, religion, history, sport, etc. The scope of philosophy includes any question that can be illumined by means of rational analysis. Historically, philosophy is among the oldest of all academic disciplines, and is the source of many other disciplines which today stand separately, from physics to psychology.
While the Christians at Colosse were warned by Paul not to be taken captive by hollow and deceptive philosophy (Colossians 2:8), Paul himself modeled careful philosophical analysis and keen awareness of the climate of thought in his day (see especially Acts 17:16-34). The use of philosophy to argue for and defend the truth of Christianity is sometimes called "apologetics." Such reasoned defenses of the faith in the last generation have created a climate where one need not feel intellectually inferior for being a Christian. Where once it was a rarity to find a first-class Christian philosopher in academia, now many of the best philosophy departments at universities across America have members of their faculties who are Christians.