“Can an instantaneous cube exist?”

“Don’t follow you,” said Filby.

“Can a cube that does not last for any time at all, have a real existence?”
Filby became pensive. “Clearly,” the Time Traveller proceeded,  “any real body
must have extension in four directions: it must have Length,  Breadth,
Thickness, and Duration. But through a natural infirmity of the flesh,  which I
will explain to you in a moment, we incline to overlook this fact. There  are
really four dimensions, three which we call the three planes of Space, and  a
fourth, Time. There is, however, a tendency to draw an unreal distinction
between the former three dimensions and the latter, because it happens that  our
consciousness moves intermittently in one direction along the latter from  the
beginning to the end of our lives.”
