anyatve 'pi vā paścād vegasya pūrvakasya vināśakāraṇābhāvāt tādavasthyamevetyapāta eva syāccharasya
Or even if [there were] difference later on in the velocity, since there would be no cause for the destruction of the prior [velocity], there should only be continuation of the same state and thus no falling of the arrow.