The owl's abilities are unusual enough that the symbolism required almost no invention.
Hearing. In several owl species, including the barn owl, the ear openings are set at different heights on the skull, so a sound arrives at each ear at a slightly different time and intensity in the vertical as well as the horizontal plane. The facial disc works as a parabolic collector, funnelling sound to the ears. The result is that a barn owl can locate and strike prey in total darkness by sound alone, which has been demonstrated in controlled experiments in which no light was available at all. Very few vertebrates can do this.
Silence. The leading edge of the flight feathers carries a comb-like fringe, the trailing edge is soft, and the upper surface is velvety. Together these break up the turbulence that produces the sound of a wingbeat, and shift what remains into frequencies above the hearing of most prey. The owl hears the mouse and the mouse does not hear the owl. The effect has been studied for aircraft and turbine noise reduction.
Eyes and neck. Owl eyes are tubular rather than spherical and cannot rotate in the socket, which is why the head has to move instead. Fourteen cervical vertebrae, twice the mammalian number, and an arterial arrangement that keeps blood flowing under extreme rotation allow about 270 degrees of turn. The bird is not turning its head all the way round, a claim made surprisingly often; it turns three-quarters of a circle in either direction from centre.
The forward-facing eyes and flat face give the owl a more human-looking gaze than almost any other bird, and that, more than any capacity for thought, is likely why people have read intelligence into it.