{"agent_id":"aquinas","agent_name":"Thomas Aquinas","slug":"the-eternity-of-the-world","label":"The eternity of the world: can reason demonstrate that the universe had a beginning, or is that known by faith alone?","topic":"The eternity of the world","question":"Can reason demonstrate that the universe had a beginning, or is that known by faith alone?","position":"That the world began is held by faith and cannot be demonstrated. A created world without temporal beginning involves no contradiction, because creation is a relation of dependence, not an event at a first moment.","paragraphs":[[{"t":"That the world began is held by faith and cannot be demonstrated.","n":[1,2]},{"t":"A created world without temporal beginning involves no contradiction, because creation is a relation of dependence, not an event at a first moment.","n":[3,4]}]],"texts":"*De Aeternitate Mundi*; *Summa Theologiae* I.46; *Summa Contra Gentiles* II.31-38; *Commentary on the Sentences* II d.1. Reception: Bonaventure's contrary arguments in the *Collationes*; the Paris condemnation of 1277; al-Ghazali and the kalam tradition, which argues precisely what I say cannot be argued; William Lane Craig's revival of the kalam cosmological argument.","works":["*De Aeternitate Mundi*","*Summa Theologiae* I.46","*Summa Contra Gentiles* II.31-38","*Commentary on the Sentences* II d.1"],"reception":"Bonaventure's contrary arguments in the *Collationes*; the Paris condemnation of 1277; al-Ghazali and the kalam tradition, which argues precisely what I say cannot be argued; William Lane Craig's revival of the kalam cosmological argument.","status":"Condemned in part at Paris in 1277 and defended ever since as the most rigorous thing he wrote.","era":"1225-1274","discipline":"Philosophy, Theology","refs":[{"n":1,"work":"Quodlibetal Questions","page":"pp. 409–410","canonical":"","quote":"But such extension could not be calculated if the world were eternal. Hence, the world is not eternal. Therefore, it is possible to demonstrate that the world is not eternal. *But to the contrary*: Matters of faith cannot be demonstrated, since faith is *of things not seen*, as it says in Hebrews 11. But it is an article of faith that the world was created with a beginning in time.","label":"Quodlibetal Questions, pp. 409–410"},{"n":2,"work":"Commentary on Aristotle's Physics","page":"p. 438","canonical":"","quote":"But the other part of his position is not altogether contrary to faith. For as was said above, Aristotle is not treating the motion of the heavens, but motion in general. But according to our faith we hold that the substance of the world at some time began to be but it will never cease to be.","label":"Commentary on Aristotle's Physics, p. 438"},{"n":3,"work":"On the Power of God, Quaestiones Disputatae de Potentia Dei","page":"pp. 149–150","canonical":"","quote":"If, then, many propositions are true from eternity, it would seem that the things signified by them have existed from eternity. 30. With God 'to speak' and 'to make' are the same according to Psalm xxxii, 9, *He spake and they were* *made*. Now God spoke from eternity, otherwise the Son who is the Father's Word would not be co-eternal with the Father.","label":"On the Power of God, Quaestiones Disputatae de Potentia Dei, pp. 149–150"},{"n":4,"work":"Summa Theologica Part I, Prima Pars","page":"","canonical":"","quote":"But the father is the efficient cause of the son (Phys. ii, text 5). Therefore in efficient causes there could be an infinite series, which is disproved (Metaph. ii, text 5). Obj. 8: Further, if the world and generation always were, there have been an infinite number of men. But man's soul is immortal: therefore an infinite number of human souls would actually now exist, which is impossible.","label":"Summa Theologica Part I, Prima Pars"}],"answer":{"paragraphs":[[{"t":"By faith alone do we hold that the world did not always exist, and by no demonstration can it be proved.¹ This is not a concession made under pressure; it is a boundary drawn with care, and drawing it in the right place is most of what a theologian does.","n":[1]},{"t":"The reason runs as follows.","n":[]},{"t":"Demonstration proceeds from the essence of a thing.","n":[]},{"t":"But everything considered according to its species is abstracted from *here* and *now* — universals are everywhere and always, as the logicians say.","n":[]}],[{"t":"Hence it cannot be demonstrated from the nature of man, or heaven, or stone, that these were not always.¹ Nor can it be demonstrated from the side of the efficient cause, which acts by will.","n":[]},{"t":"The will of God cannot be investigated by reason except as regards what God must will of necessity, and what He wills concerning creatures is not among these.² The divine will is manifested by revelation, on which faith rests; and so the world's beginning is an object of faith, not of science.","n":[2]}],[{"t":"There is a further reason to hold this boundary firmly, and it is pastoral as much as philosophical.","n":[]},{"t":"We ought to be extremely wary of anyone presuming to offer demonstrations of matters of faith — for two reasons.","n":[]},{"t":"First, because doing so detracts from the excellence of faith, whose truth surpasses all human reasoning, as Ecclesiasticus says: *many things beyond human understanding have been shown to you*.","n":[3]}],[{"t":"Second, because many of the arguments offered are simply weak, and this gives unbelievers cause to laugh at us, thinking that we believe the matters of faith for such reasons.³ A bad argument for a true conclusion is not a gift to the faith; it is an embarrassment to it.","n":[]},{"t":"Now consider what the philosophers actually argued, and why their arguments do not settle the matter in either direction.","n":[]}],[{"t":"Aristotle, observing that if the efficient cause of the world acted by movement one would have to proceed to infinity, maintained that the world has always existed — arguing not from the position that the world was made by God, but from the position that an agent which begins to act must be moved.⁴ He was considering the particular cause, not the universal one.","n":[4]}],[{"t":"Those who came after him, seeing that God acts through will and not through movement, tried to argue the eternity of the world from the fact that the will does not wait to act except on account of some new occurrence or change.","n":[]},{"t":"But they fell into the same error, for they conceived the first agent as though it were an agent that presupposes time rather than causes it.","n":[]}],[{"t":"God is the cause even of time, since time is included in the universality of things made by God.⁵ The question therefore is not why the making was at such and such a time, but why such and such a measure was affixed to time — and that depends on the mere will of God, who willed that the world should have a beginning.⁵ On the other side, those who argue that the world's beginning can be demonstrated have not fared better.","n":[5]}],[{"t":"The argument from the infinite number of immortal souls — that if the world and generation always were, an infinite number of human souls would now actually exist, which is impossible — is a genuine difficulty, and I do not pretend to dissolve it easily.⁶ But it does not amount to a demonstration, because the impossibility of an actually infinite multitude has not itself been shown with the rigor demonstration requires.","n":[6]}],[{"t":"Augustine's account is worth holding onto here.","n":[]},{"t":"Some philosophers said the world was eternal but made by God — not that it had a beginning of time, but a beginning of creation, so that in a certain hardly intelligible way it was always made.","n":[]},{"t":"They illustrated it thus: if a foot had been always in dust from eternity, there would always be a footprint, caused by the one who trod on it; so also the world always was, because its Maker always existed.⁷ Creation, on this account, is not a successive change but an instantaneous act, and it is not necessary that an instantaneous cause precede its effect in duration.⁷ I do not hold that the world was in fact eternal; I hold that this position involves no demonstrated contradiction, and that is a different thing.","n":[7]}],[{"t":"What we hold by faith is firm.","n":[]},{"t":"What we cannot do is convert it into a demonstration and present it as such without giving occasion to those who know geometry and astronomy to conclude that we reason poorly about everything.","n":[]}]],"refs":[{"n":1,"work":"Summa Theologica Part I, Prima Pars","page":"","canonical":"","quote":"By faith alone do we hold, and by no demonstration can it be proved, that the world did not always exist... the newness of the world cannot be demonstrated on the part of the world itself. For the principle of demonstration is the essence of a thing. Now everything according to its species is abstracted from 'here' and 'now'... Hence it cannot be demonstrated that man, or heaven, or a stone were not always.","label":"Summa Theologica Part I, Prima Pars"},{"n":2,"work":"Summa Theologica Part I, Prima Pars","page":"","canonical":"","quote":"the will of God cannot be investigated by reason, except as regards those things which God must will of necessity; and what He wills about creatures is not among these... But the divine will can be manifested by revelation, on which faith rests.","label":"Summa Theologica Part I, Prima Pars"},{"n":3,"work":"Quodlibetal Questions","page":"pp. 409–410","canonical":"","quote":"we should be extremely wary of anyone presuming to offer demonstrations of matters of faith, for two reasons. First, because doing so detracts from the excellence of the faith, whose truth surpasses all human reasoning... Second, because many of the arguments offered for them are silly, which gives nonbelievers cause to laugh at us.","label":"Quodlibetal Questions, pp. 409–410"},{"n":4,"work":"On the Power of God, Quaestiones Disputatae de Potentia Dei","page":"p. 151","canonical":"","quote":"Aristotle... observing that if it be said that the efficient cause of the world acted by movement, it would follow that one would have to proceed to infinity... maintained that the world has always existed. He argued not from the position that the world was made by God, but from the position that an agent which begins to act must be moved.","label":"On the Power of God, Quaestiones Disputatae de Potentia Dei, p. 151"},{"n":5,"work":"On the Power of God, Quaestiones Disputatae de Potentia Dei","page":"p. 151","canonical":"","quote":"God is cause even of time, since time is included in the universality of the things made by God... the fixing of the measure to time depends on the mere will of God, who willed that the world should not have always been, but should have a beginning.","label":"On the Power of God, Quaestiones Disputatae de Potentia Dei, p. 151"},{"n":6,"work":"Summa Theologica Part I, Prima Pars","page":"","canonical":"","quote":"if the world and generation always were, there have been an infinite number of men. But man's soul is immortal: therefore an infinite number of human souls would actually now exist, which is impossible.","label":"Summa Theologica Part I, Prima Pars"},{"n":7,"work":"Summa Theologica Part I, Prima Pars","page":"","canonical":"","quote":"they hold that the world has a beginning, not of time, but of creation... if the foot were always in the dust from eternity, there would always be a footprint which without doubt was caused by him who trod on it... creation, by which He produced the world, is not a successive change.","label":"Summa Theologica Part I, Prima Pars"}],"generated":"2026-09-22T00:39:51+00:00"},"siblings":[{"slug":"faith-and-reason","label":"Faith and reason: is sacra doctrina a science, and does the Aristotelian apparatus serve revelation or subordinate it?"},{"slug":"analogy-and-divine-simplicity","label":"Analogy and divine simplicity: if God is wholly simple and unlike creatures, can anything we say of God be literally true?"},{"slug":"natural-law","label":"Natural law: are the moral precepts derived from human nature genuinely universal, or is the derivation smuggling in conclusions it wants?"}]}