Tertullian, A Treatise on the Soul 30

So what do we say to the rest of the objections? First: if the living come from the dead just as the dead come from the living, one single, identical headcount of all humanity would have stayed frozen forever—the exact number that first stepped into life. The living come first, then the dead from the living, then the living again from the dead. While this cycle spins from the same pool, the tally coming out always matches the tally going in; not one more, not one fewer would have exited than returned. But the records of human antiquity tell a different story: the race has steadily swollen. Indigenous peoples, wanderers, exiles, and glorious conquerors alike have seized territories—Scythians in Parthia, Amyclae in the Peloponnese, Athenians in Asia, Phrygians in Italy, Phoenicians in Africa. Organized migrations, the so-called apoikiai, deliberately poured surplus populations into new frontiers. The original inhabitants still hold their ground, yet they have also loaned their stock abroad. The world itself lies open before us, more cultivated and better mapped with each passing day. Every route is passable, every region known, every corner open for business. Famous wildernesses have vanished under pleasant estates; forests have yielded to fields; wild beasts have fled before cattle; sands are sown, rocks planted, marshes drained. Cities now rise where not even huts once stood. Islands no longer repel, cliffs no longer terrify; everywhere houses, everywhere people, everywhere government, everywhere life. The supreme proof of human density: we are a burden on the world. The elements barely cover our needs, necessities pinch tighter, complaints rise on all sides, because nature no longer sustains us. Pestilence, famine, wars, the swallowing of cities—these count as remedies, a pruning of the overgrown human race. Yet when such axes once hack down the greatest mass of mortals, they never bring it back by raising the living from the dead; after a thousand years the world once shuddered at depopulation. If the living were made from the dead, that equal force of loss and restoration would have been palpable. Why, then, a thousand years later and not at once? If what is paid out is not instantly replenished, the whole stock risks being consumed, since restoration would be pre-empted by the collapse; the provisions of this life could never stretch to a thousand years—far too short a span, and therefore easier to extinguish than to rekindle. So what would have collapsed in that scenario, if the living came from the dead, has not collapsed; therefore it will not be believed that the living come from the dead.