New facts are constantly developing in this science, as in others, which enable us to verify the facts and principles heretofore accepted, when true, and to modify them when erroneous. New theories present themselves for the better explanation of facts already known, and are tested by these, and by others subsequently discovered, and are received or rejected, according to their ascertained correctness. The knowledge of the past is built upon for progression towards the future. The discovery of the facts is conducted, as in all other sciences, by study of what the field affords. Geology examines the earth, and derives its facts from the structure of that earth.
Astronomy investigates the stars.
Theology, likewise, studies the sources of its knowledge. Each science seeks to arrive at the truth. The votaries of each are certain that it is to be found in their fields, either partially, or completely. The perfect attainment of all facts prepares for the exactness of scientific knowledge. The absence of any must make the knowledge incomplete.