An inquiry about God without referring to divine revelation, Natural
Theology actually has ancient roots--going back to the ancient Greek
philosophers. Even more specific, Natural Theology can be traced
back to the pre-Socratics, who quested after the "first principle of
things." Like today, these early philosophers were trying (or hoping)
to understand Ultimate Reality. the Source of all things.
Unlike us moderns, these ancient philosophers did not have the
advantage of contemporary Science or its adjunct Technology.
Mainly their effort relied on being "purely rational." And in their
way, working with their minds, these early questers actually can
be proved scientifically correct in some of their calculations
about their circumstance, even about their observations about
the Cosmos.
In our own time Natural Theology perhaps takes another course,
not necessarily trying to explain a First Principle, if you will. Today
this theological approach is not necessarily one that tries to prove
that God exists--though, for some, Natural Theology does pursue
a transcendent reality in which we humans exist. It's about the
universe in which we live and have our being. Basically its approach
is philosophically familiar, in that it is both cosmologically
and ontologically oriented.
Still, for those who do believe in God this approach by Natural
Theology can point to a Creator. It's also about a synthesis of
human knowledge that can cover a myriad of disciplines, not only
from Science, but also from Religion and Spirituality, the Arts, and
Philosophy. Natural Theology involves an integrative approach
and, most importantly, employs our modern knowledge-base!