Natural Theology, is a branch of theology that is defined as one that is "based on reason and ordinary experience." (Wikipedia) It tends to be highly philosophical in nature, and often makes little or no use of the Biblical texts as a foundation for its argumentation (although, it often points to a Biblical verse to validate the conclusion, but the passage itself is not typically used as a supporting part of the argument. This is in contrast with Revealed Theology which is based on scripture.