In a similar way we may conceive that progress may be made in natural theology in either of two ways: by deducing consequences from what we know or observe, or by assuming for trial the truth of a
statement made on whatever authority it may be, and then examining whether the supposition of its truth so falls in with such knowledge as we possess, or such phenomena as we observe, as to lead us to a conviction that the statement does indeed express the truth. It may be that the statement comes from a source which professes to be a revelation made from God to man. But such an employment of it as I have just described is strictly analogous to our procedure in the study of physical science, and does not therefore seem to be precluded by the terms of the foundation of this lectureship.