in his book "a history of man", hubbard referred to the bubble gum incident as "the fly trap": "very, very early on the track, a long time before the present populace came into being, there was a theta trap called the fly trap. it was of a gummy material... also called the 'bubble gum' incident, because every time a thetan pushes against it, it pushes back and it finally gives him an obsession about motion".