Systems which have universally owed their origin to the lucubrations of those who were acquainted with one art, but ignorant of the other; who therefore explained to themselves the phenomena, in that which was strange to them, by those in that which was familiar; and with whom, upon that account, the analogy, which in other writers gives occasion to a few ingenious similitudes, became the great hinge on which every thing turned.
ADAM SMITH, Essay on the History of Astronomy