Cap. X Arg. III: if reprobation hung on foreseen final impenitence/unbelief, no one would be reprobated except considered as dying — even as dead — because final perseverance/pertinacity is not fulfilled while we still live
Suppose the reprobation decree hung on the reprobates' foreseen final impenitence and unbelief. Then no one would be reprobated except as God considered him dying — nay, dead. Why is that plain? Because while life is lived here, neither anyone's final perseverance in faith, nor final pertinacity in unbelief, is fulfilled. Whatever comes before the end is only a step by which one climbs toward the summit, not the term by which the height's top is already held.
Latin
Si decretum reprobationis penderet ex praevisa finali impoenitentia et infidelitate reprobatorum, tum nemo reprobaretur nisi consideratus a Deo ut moribundus, imo ut mortuus. Ratio perspicua est; Quia dum hic vivitur, neque finalis cujusquam perseverantia in fide, neque finalis pertinacia in infidelitate adimpletur. Quicquid enim ante finem fuerit, gradus est quo ad fastigium ascenditur, non terminus quo jam culminis summa teneatur.