“We should be proceeding precisely on the lines of Copernicus primary assumption. Failing of satisfactory progress in explaining the movements of the heavenly bodies on the supposition that they all revolved around the observer, he tried whether he might not have a better success if he made the observer to revolve and the stars to remain at rest”. This famous sentence appears in the preface to the second edition of the Critique of Pure Reason (1787), one of the most influential book of all times, authored by philosopher Immanuel Kant, who tried a similar experiment in metaphysics, as regards the a priori knowledge of the objects of the senses. Actually, swapping the two possible and complementary points of view about the same problem is a powerful way to find new solutions in all fields of human knowledge. When this happens, a true Copernican revolution takes place.
Likewise, in engineering science, direct problems are defined as those where, given the input or the cause of a phenomenon or of a process in a device, the purpose is that of finding the output or the effect.