By the 19th century, the debate was generally considered to have been settled in favor of the wave theory, as it was able to explain observed effects such as refraction, diffraction, interference, and polarization.
V priebehu 19. storočia sa táto diskusia všeobecne považovala za uzavretú v prospech vlnenia, pretože dokázala vysvetliť pozorované javy ako lom, difrakciu a polarizáciu.