I did wonder at the discrepancy at the time, so I re-listened to the audio several times carefully when I was writing the transcript above.  To me, he is clearly saying <i>gee</i> rather than <i>vee</i> (could be an artifact of the recording though).<p>I&#x27;m sure Hillis knows more physics than I do (though I knew the equations of motion pretty well at one time), but he could easily have just mis-spoke.  I didn&#x27;t pursue this line of thought, but considered it might have been something to do with him deriving an expression for the vertical position in a gravitational field, perhaps in terms of horizontal motion or something.