The Greek philosopher Plato presented the Allegory of the Cave in his work The Republic. The allegory is related to Plato's Theory of Forms. The material world is known to us through sensation. Plato's Forms possess the highest and most fundamental kind of reality. In mathematical terms, we perceive the material world by means of remote sensing. For example, physicists see images in the bubble chamber, but not the elementary particles themselves. Geophysicists see seismic images, but not the underground earth itself. The received images correspond to Plato's shadows. Historically...

By the late 1940s it was becoming increasingly difficult to discover petroleum. The analog geophysical methods gave results so poor that success largely depended upon drilling well after well until one hit oil. In 1948, MIT researchers under the guidance of Professor Norbert Wiener decided to investigate the problem. In 1950 seismograms that were recorded as traces on photographic paper were digitized at MIT by ruler and pencil. Various digital methods were tried until it was discovered that deconvolution worked. By 1952 the method was programmed on the Whirlwind digital computer, and the MIT...