The question of whether a device will come into being depends upon three things: first, whether there is a practical use for it that warrants its development and manufacturing costs; second, whether the laws of physics applying to the elements available for its design allow the attainment of the needed ranges, sensitivities, or the like; and third, whether the pertinent art of manufacture has advanced sufficiently to allow a useful embodiment to be built successfully.
Vannevar BushA belief may be larger than a fact. A faith that is overdefined is the very faith most likely to prove inadequate to the great moments of life.
Vannevar BushThe camera hound of the future wears on his forehead a lump a little larger than a walnut.
Vannevar BushWholly new forms of encyclopedias will appear, ready made with a mesh of associative trails running through them, ready to be dropped into the memex and there amplified.
Vannevar Bush