Principia

So it may be best to think of theology and philosophy in terms of the historical notion of principia. The word principium, at least historically, is the Latin translation of the Greek word arche, which means "source," or "cause," or "foundation." It is that which gives something its reason to be, or its justification for existence. Under this rubric distinctions have been made between a principium essendi and a principium cognoscendi.' There are essential principles, reasons, or sources; and there are epistemological principles, reasons, or sources.

 

Scott Oliphint. Reasons for Faith: Philosophy in the Service of Theology (Phillipsburg, NJ: PR Publishing, 2006), 25