"In such cases the inductive and deductive methods of inquiry may be said to go hand in hand, the one verifying the conclusions deduced by the other; and the combination of experiment and theory, which may thus be brought to bear in such cases, forms an engine of discovery infinitely more powerful
than either taken separately. This state of any department of science is perhaps of all others the most interesting, and that which promises the most to research."—SIR J. HERSCHEL, Discourse on the Study of Natural Philosophy.