Exposed by autoreference

W. L. Bragg, the pioneer in x-ray diffraction, gave this loose but vivid interpretation: "The dividing line between the wave and particle nature of matter and radiation is the moment 'now'. As this moment steadily advances through time it coagulates a wavy future into a particle past... Everything in the future is wave, everything in the past is a particle." If the "moment 'now'" is understood to be the time a measurement is performed, this is a reasonable way to think about the situation. (The philosopher Soren Kierkegaard may have been anticipating this aspect of modern physics when he wrote, "Life can only be understood backwards, but it must be lived forwards.")

Arthur Beisler, Concepts of modern physics, 2003. La paja en el ojo ajeno y la viga en el propio.