For example, in the familiar  phenomenon
of seeing an object by our eye, both descriptions are
important The gathering and focussing mechanism of
light by the eye-lens is well described in the wave picture But its absorption by the rods and cones (of the retina)
requires the photon picture of light A natural question arises: If radiation has a dual (wave-
particle) nature, might not the particles of nature (the
electrons, protons, etc