No ancient handbook reads the motor car, which is precisely what makes it useful: the car shows dream symbolism being made in the open. Within a generation of the automobile's spread it had become one of the most frequent objects in collected dream reports, and the content analysis tradition founded by Calvin Hall, counting the elements of thousands of dreams, found vehicles among the standard furniture of modern dreaming. The continuity hypothesis in dream research, that dreams work over the stuff of waking life, needs no better exhibit.
The car did not arrive without ancestors. The older literatures read the chariot, the carriage, the horse and the ship by the same questions interpreters now put to the car: who holds the reins or the wheel, does the vehicle answer, where is the road going. The chariot of the soul in Plato's Phaedrus, with reason driving two unruly horses, is the image's philosophical grandparent, and the ship's helm served the old handbooks as the standing figure of a life under or out of control.
The modern readings follow directly. Driving, being driven, brakes that fail, a wheel that will not turn: interpreters across schools read these as the dreamer's report on agency, on who is steering a life and how well the controls answer. The reading is recent, its logic old.