The concept of causation is a principal underpinning idea in all cosmological arguments, particularly in affirming the necessity for a First Cause. The latter is typically determined in philosophical analysis to be God, as identified within classical conceptions of theism.
The origins of the argument date back to at least Aristotle, developed subsequently within the scholarly traditions of Neoplatonism and early Christianity, and later under medieval Islamic scholasticism through the 9th to 12th centuries. It would eventually be re-introduced to Christian theology in the 13th century by Thomas Aquinas. In the 18th century, it would become associated with the principle of sufficient reason formulated by Gottfried Leibniz and Samuel Clarke, itself an exposition of the Parmenidean causal principle that "nothing comes from nothing".
Contemporary defenders of cosmological arguments include William Lane Craig, Robert Koons, John Lennox, Stephen Meyer, and Alexander Pruss.
History
Classical philosophy
Plato (c. 427–347 BC) and Aristotle (c. 384–322 BC) both posited first cause arguments, though each had certain notable caveats. In The Laws (Book X), Plato posited that all movement in the world and the Cosmos was "imparted motion". This required a "self-originated motion" to set it in motion and to maintain it. In Timaeus, Plato posited a "demiurge" of supreme wisdom and intelligence as the creator of the Cosmos.
Aristotle argued against the idea of a first cause, often confused with the idea of a "prime mover" or "unmoved mover" (πρῶτον κινοῦν ἀκίνητον or primus motor) in his Physics and Metaphysics. Aristotle argued in favor of the idea of several unmoved movers, one powering each celestial sphere, which he believed lived beyond the sphere of the fixed stars, and explained why motion in the universe (which he believed was eternal) had continued for an infinite period of time. Aristotle argued the atomist's assertion of a non-eternal universe would require a first uncaused cause – in his terminology, an efficient first cause – an idea he considered a nonsensical flaw in the reasoning of the atomists.
Like Plato, Aristotle believed in an eternal cosmos with no beginning and no end (which in turn follows Parmenides' famous statement that "nothing comes from nothing"). In what he called "first philosophy" or metaphysics, Aristotle did intend a theological correspondence between the prime mover and a deity; functionally, however, he provided an explanation for the apparent motion of the "fixed stars" (now understood as the daily rotation of the Earth). According to his theses, immaterial unmoved movers are eternal unchangeable beings that constantly think about thinking, but being immaterial, they are incapable of interacting with the cosmos and have no knowledge of what transpires therein. From an "aspiration or desire", the celestial spheres, imitate that purely intellectual activity as best they can, by uniform circular motion. The unmoved movers inspiring the planetary spheres are no different in kind from the prime mover, they merely suffer a dependency of relation to the prime mover. Correspondingly, the motions of the planets are subordinate to the motion inspired by the prime mover in the sphere of fixed stars. Aristotle's natural theology admitted no creation or capriciousness from the immortal pantheon, but maintained a defense against dangerous charges of impiety.
Plotinus, a third-century Platonist, taught that the One transcendent absolute caused the universe to exist simply as a consequence of its existence (creatio ex deo). His disciple Proclus stated "The One is God". Centuries later, the Islamic philosopher Avicenna (c. 980–1037) inquired into the question of being, in which he distinguished between essence (māhiyya) and existence (wuǧūd). He argued that the fact of existence could not be inferred from or accounted for by the essence of existing things, and that form and matter by themselves could not originate and interact with the movement of the Universe or the progressive actualization of existing things. Thus, he reasoned that existence must be due to an agent cause that necessitates, imparts, gives, or adds existence to an essence. To do so, the cause must coexist with its effect and be an existing thing.
Early Christian theology
Steven Duncan writes that the cosmological argument "was first formulated by a Greek-speaking Syriac Christian neo-Platonist, John Philoponus, who claims to find a contradiction between the Greek pagan insistence on the eternity of the world and the Aristotelian rejection of the existence of any actual infinite". Referring to the argument as the "'Kalam' cosmological argument", Duncan asserts that it "received its fullest articulation at the hands of [medieval] Muslim and Jewish exponents of Kalam ("the use of reason by believers to justify the basic metaphysical presuppositions of the faith").
Thomas Aquinas (c. 1225–1274) adapted and enhanced the argument he found in his reading of Aristotle, Avicenna (the Proof of the Truthful), and Maimonides to form one of the most influential versions of the cosmological argument. His conception of first cause was the idea that the Universe must be caused by something that is itself uncaused, which he claimed is that which we call God:
The second way is from the nature of the efficient cause. In the world of sense we find there is an order of efficient causes. There is no case known (neither is it, indeed, possible) in which a thing is found to be the efficient cause of itself; for so it would be prior to itself, which is impossible. Now in efficient causes it is not possible to go on to infinity, because in all efficient causes following in order, the first is the cause of the intermediate cause, and the intermediate is the cause of the ultimate cause, whether the intermediate cause be several, or only one. Now to take away the cause is to take away the effect. Therefore, if there be no first cause among efficient causes, there will be no ultimate, nor any intermediate cause. But if in efficient causes it is possible to go on to infinity, there will be no first efficient cause, neither will there be an ultimate effect, nor any intermediate efficient causes; all of which is plainly false. Therefore it is necessary to admit a first efficient cause, to which everyone gives the name of God.
Importantly, Aquinas' Five Ways, given the second question of his Summa Theologica, are not the entirety of Aquinas' demonstration that the Christian God exists. The Five Ways form only the beginning of Aquinas' Treatise on the Divine Nature.
General principles
The infinite regress
A regress is a series of related elements, arranged in some type of sequence of succession, examined in backwards succession (regression) from a fixed point of reference. Depending on the type of regress, this retrograde examination may take the form of recursive analysis, in which the elements in a series are studied as products of prior, often simpler, elements. If there is no 'last member' in a regress (ie. no 'first member' in the series) it becomes an infinite regress, continuing in perpetuity. In the context of the cosmological argument the term 'regress' usually refers to causal regress, in which the series is a chain of cause and effect, with each element in the series arising from causal activity of the prior member. Some variants of the argument may also refer to temporal regress, wherein the elements are past events (discrete units of time) arranged in a temporal sequence.
An infinite regress argument attempts to establish the falsity of a proposition by showing that it entails an infinite regress that is vicious. The cosmological argument is a type of positive infinite regress argument given that it defends a proposition (in this case, the existence of a first cause) by arguing that its negation would lead to a vicious regress. An infinite regress may be vicious due to various reasons:
- Impossibility: Thought experiments such as Hilbert's Hotel are cited to demonstrate the metaphysical impossibilty of actual infinities existing in reality. By the same token, it may be argued that an infinite causal or temporal regress cannot occur in the real world.
- Implausibility: The regress contradicts empirical evidence (eg. for the finitude of the past) or basic principles such as Occam's razor.
- Explanatory failure: A failure of explanatory goals resulting in an infinite regress of explanations. This may arise in the case of logical fallacies such as begging the question or from an attempt to investigate causes concerning origins or fundamental principles.
Accidental and essential ordering of causes
Aquinas refers to the distinction found in Aristotle's Physics (8.5) that a series of causes may either be accidental or essential, though the designation of this terminology would follow later under John Duns Scotus at the turn of the 14th century.
In an accidentally ordered series of causes, earlier members need not continue exerting causal activity (having done so to progress the chain) for the series to continue. For example, in an ancestral lineage, the ancestors need no longer exist in order for their descendents to resume the bloodline. In an essential series, every prior member must maintain causal interrelationship in order for the series to continue: If a hand holds a stick that moves a rock along the ground, the rock would stop motion as soon as the hand or stick ceases to exist.
Based upon this distinction Frederick Copleston (1907-1994) characterises two types of causation: Causes in fieri, which cause an effect's becoming, or coming into existence, and causes in esse, which causally sustain an effect, in being, once it exists.
Two specific properties of an essentially ordered series have significance in the context of the cosmological argument:
- A first cause is essential: In the example illustrated above, the rock derives its causal power essentially from the stick, which derives its causal power essentially from the hand. Later members exercise no independent causal power in continuing the causal series.
- It requires that all causes in the series exist simultaneously in time, or timelessly.
Thomistic philosopher, R. P. Phillips comments on the characteristics of essential ordering:
- "Each member of the series of causes possesses being solely by virtue of the actual present operation of a superior cause ... Life is dependent inter alia on a certain atmospheric pressure, this again on the continual operation of physical forces, whose being and operation depends on the position of the earth in the solar system, which itself must endure relatively unchanged, a state of being which can only be continuously produced by a definite—if unknown—constitution of the material universe. This constitution, however, cannot be its own cause ... We are thus irresistibly led to posit a first efficient cause which, while itself uncaused, shall impart causality to a whole series."
Versions of the argument
Aquinas's argument from contingency
In the scholastic era, Aquinas formulated the "argument from contingency", following Aristotle, in claiming that there must be something to explain the existence of the universe. Since the universe could, under different circumstances, conceivably not exist (ie. it is contingent) its existence must have a cause. This cause cannot be embodied in another contingent thing, but something that exists by necessity (ie. that must exist in order for anything else to exist). It is a form of argument from universal causation, therefore compatible with the conception of a universe that has no beginning in time. In other words, according to Aquinas, even if the universe has always existed, it still owes its continuing existence to an uncaused cause, he states: "... and this we understand to be God."
Aquinas's argument from contingency is formulated as the Third Way (Q2, A3) in the Summa Theologica. It may be expressed as follows:
- There exist contingent things, for which non-existence is possible.
- It is impossible for contingent things to always exist, so at some time they do not exist.
- Therefore, if all things are contingent, then nothing would exist now.
- There exists something rather than nothing.
He concludes thereupon that contingent beings are an insufficient explanation for the existence of other contingent beings. Furthermore, that there must exist a necessary being, whose non-existence is impossible, to explain the origination of all contingent beings.
- Therefore, there exists a necessary being.
- It is possible that a necessary being has a cause of its necessity in another necessary being.
- The derivation of necessity between beings cannot regress to infinity (being an essentially ordered causal series).
- Therefore, there exists a being that is necessary of itself, from which all necessity derives.
- That being is whom everyone calls God.
Leibnizian cosmological argument
In 1714, German philosopher Gottfried Leibniz presented a variation of the cosmological argument based upon the principle of sufficient reason. He writes: "There can be found no fact that is true or existent, or any true proposition, without there being a sufficient reason for its being so and not otherwise, although we cannot know these reasons in most cases." Stating his argument succinctly:
- "Why is there something rather than nothing? The sufficient reason ... is found in a substance which ... is a necessary being bearing the reason for its existence within itself."
Alexander Pruss formulates the argument as follows:
- Every contingent fact has an explanation.
- There is a contingent fact that includes all other contingent facts.
- Therefore, there is an explanation of this fact.
- This explanation must involve a necessary being.
- This necessary being is God.
Premise 1 expresses the principle of sufficient reason (PSR). In premise 2, Leibniz proposes the existence of a logical conjunction of all contingent facts. This may be regarded as the sum total of all contingent reality, referred to in later literature as the Big Conjunctive Contingent Fact (BCCF). Premise 3 applies the PSR to the BCCF, given that it too, as a contingency, has a sufficient explanation. It follows, in statement 4, that the explanation of the BCCF must be necessary, not contingent, given that the BCCF incorporates all contingent facts.
Statement 5 proposes that the necessary being explaining the totality of contingent facts is God. Philosophers of religion, such as Joshua Rasmussen and T. Ryan Byerly, have argued in defence of the inference from 4 to 5.
Duns Scotus's argument
Inspired by Aquinas's argument of the unmoved mover, this metaphysical argument for the existence of God was formulated by influential Medieval Christian theologian Duns Scotus (1265/66–1308). Like other philosophers and theologians, Scotus believed that his statement for God's existence could be considered separate to that of Aquinas. The form of the argument can be summarised as follows:
- An effect cannot be produced by itself.
- An effect cannot be produced by nothing.
- A circle of causes is impossible.
- Therefore, an effect must be produced by something else.
- An accidentally ordered causal series cannot exist without an essentially ordered series.
- Each member in an accidentally ordered series (except a possible first) exists via causal activity of a prior member.
- That causal activity is exercised by virtue of a certain form.
- Therefore, that form is required by each member to effect causation.
- The form itself is not a member of the series.
- Therefore [c,d], accidentally ordered causes cannot exist without higher-order (essentially ordered) causes.
- An essentially ordered causal series cannot regress to infinity.
- Therefore [4,5,6], there exists a first agent.
Scotus affirms, in premise 5, that an accidentally ordered series of causes is impossible without higher-order laws and processes that govern the basic nature of all causal activity, which he characterises as essentially ordered causes. Premise 6 continues, in accordance with Aquinas's discourses on the Second Way and Third Way, that an essentially ordered series of causes cannot be an infinite regress.
On this he posits that, if it is merely possible that a first agent exists, then it is necessarily true that a first agent exists, given that the non-existence of a first agent entails the impossibility of its own existence (by virtue of being a first cause in the chain). Establishing this as basis, he argues that it is not impossible for a being to exist that is causeless by virtue of ontological perfection.
With the formulation of this argument, Scotus establishes the first component of his 'triple primacy': The characterisation of a being that is first in efficient causality, final causality and pre-eminence, or maximal excellence, which he ascribes to God.
Kalam cosmological argument
A modern formulation of the cosmological argument that proposes, as its central thesis, the impossibility of an infinite temporal regress of events (or a past-eternal universe). Its premises defend the finitude of the past through both philosophical and scientific arguments. Many of these ideas originate in the writings of early Christian theologian John Philoponus (490–570 AD), developed within the proceedings of medieval Islamic scholasticism through the 9th to 12th centuries, eventually returning to Christian theological scholarship in the 13th century.
They were revitalised for modern academic discourse by philosopher and theologian William Lane Craig through publications such as The Kalām Cosmological Argument (1979) and the Blackwell Companion to Natural Theology (2009). The form of the argument popularised by Craig is expressed in two parts, as an initial deductive syllogism followed by philosophical analysis of its conclusion.
Initial syllogism
- Everything that begins to exist has a cause.
- The universe began to exist.
- Therefore, the universe has a cause.
Philosophical analysis of the conclusion
Craig argues that the cause of the universe necessarily embodies specific properties in creating the universe ex nihilo and in effecting creation from a timeless state (implying free agency). Based upon this analysis, he appends a further premise and conclusion:
- If the universe has a cause, then an uncaused, personal Creator of the universe exists who sans (without) the universe is beginningless, changeless, immaterial, timeless, spaceless and enormously powerful.
- Therefore, an uncaused, personal Creator of the universe exists, who sans the universe is beginningless, changeless, immaterial, timeless, spaceless and enormously powerful.
For scientific evidence of the finitude of the past, Craig appeals to the Borde-Guth-Vilenkin theorem, which posits a past boundary to cosmic inflation, and the general consensus on the standard model of cosmology, referring to the origin of the universe in the Big Bang.
For philosophical evidence, he cites the Hilbert's Hotel thought experiment and the tale of Tristram Shandy as proofs (respectively) of the impossibility of actual infinities existing in reality and of forming an actual infinite by successive addition. He concludes that past events, comprising a series of events that are, (a) instantiated in reality, (b) formed by successive addition, cannot be actually infinite.
He remarks upon the theological implications that follow from the final conclusion of this argument:
- "... our whole universe was caused to exist by something beyond it and greater than it. For it is no secret that one of the most important conceptions of what theists mean by 'God' is Creator of heaven and earth."
Criticism and discourse
"What caused the first cause?"
One objection to the argument asks why a first cause is unique in that it does not require any causes. Proponents argue that the first cause is exempt from having a cause, as this is part of what it is to be the first cause, while opponents argue that this is special pleading or otherwise untrue. Critics often press that arguing for the first cause's exemption raises the question of why the first cause is indeed exempt, whereas defenders maintain that this question has been answered by the various arguments, emphasizing that none of the major cosmological arguments rests on the premise that everything has a cause, and so the question does not address the actual premises of an argument and rests on a misunderstanding of them.
Andrew Loke states that, according to the Kalam cosmological argument, only things which begin to exist require a cause. On the other hand, something that is without beginning has always existed and therefore does not require a cause. Loke and William Lane Craig argue that an infinite regress of causes is impossible, therefore, that there must be a first uncaused cause, even if one posits a plurality of causes of the universe. Craig argues further that Occam's razor may be employed to remove unneeded further causes of the universe to leave a single uncaused cause.
"Why can't the universe be causeless?"
It is argued that the premise of causality has been arrived at via a posteriori (inductive) reasoning, which is dependent on experience. David Hume highlighted this problem of induction and argued that causal relations are not true a priori. However, as to whether inductive or deductive reasoning is more valuable remains a matter of debate, with the general conclusion being that neither is prominent. Opponents of the cosmological argument argue that it is unwise to draw conclusions from an extrapolation of causality beyond experience, therefore, that the causal principle does not apply to the origin of the universe.
Philosopher Robert Koons argues that to deny causation is to deny all empirical ideas – for example, if we know our own hand, we know it because of the chain of causes including light being reflected upon one's eyes, stimulating the retina and sending a message through the optic nerve into your brain. He summarised the purpose of the argument as "that if you don't buy into theistic metaphysics, you're undermining empirical science. The two grew up together historically and are culturally and philosophically inter-dependent ... If you say I just don't buy this causality principle – that's going to be a big big problem for empirical science."
"Why should the cause be God?"
According to this objection, the basic cosmological argument merely establishes that a first cause exists, not that it has the attributes of a theistic god, such as omniscience, omnipotence, and omnibenevolence. This is why the argument is often expanded to assert that at least some of these attributes are necessarily true, for instance in the modern Kalam argument given above.
Defenders of the cosmological arguments also reply that theologians of note are aware of the need to additionally prove other attributes of the first cause beyond that one exists. One notable example of this is found in Aquinas' Summa Theologiae in which much of the first part (Prima Pars) is devoted to establishing the attributes of this first cause, such as its uniqueness, perfection, and intelligence. Thus defenders of cosmological arguments would reply that while it is true that the cosmological argument only establishes a first cause, this is merely the first step which then allows for the demonstration of the other theistic attributes.
Timeless origin of the universe
Some cosmologists and physicists, such as Carlo Rovelli, argue that a challenge to the cosmological argument is the nature of time: "One finds that time just disappears from the Wheeler–DeWitt equation." The Big Bang theory states that it is the point in which all dimensions came into existence, the start of both space and time. Then, the question "What was there before the Universe?" makes no sense; the concept of "before" becomes meaningless when considering a situation without time.[61] This has been put forward by J. Richard Gott III, James E. Gunn, David N. Schramm, and Beatrice Tinsley, who said that asking what occurred before the Big Bang is like asking what is north of the North Pole. However, some cosmologists and physicists attempt to investigate causes for the Big Bang, using such scenarios as the collision of membranes. Philosopher Edward Feser argues that most of the classical philosophers' cosmological arguments for the existence of God do not depend on the Big Bang or whether the universe had a beginning. The question is not about what got things started, or how long they have been going, but rather what keeps them going.
Avoiding an infinite regress
David Hume and later Paul Edwards have invoked a similar principle in their criticisms of the cosmological argument. William L. Rowe has called this the Hume-Edwards principle:
If the existence of every member of a set is explained, the existence of that set is thereby explained.
Nevertheless, David White argues that the notion of an infinite causal regress providing a proper explanation is fallacious. Furthermore, in Hume's Dialogues Concerning Natural Religion, the character Demea states that even if the succession of causes is infinite, the whole chain still requires a cause. To explain this, suppose there exists a causal chain of infinite contingent beings. If one asks the question, "Why are there any contingent beings at all?", it does not help to be told that "There are contingent beings because other contingent beings caused them." That answer would just presuppose additional contingent beings. An adequate explanation of why some contingent beings exist would invoke a different sort of being, a necessary being that is not contingent. A response might suppose each individual is contingent but the infinite chain as a whole is not, or the whole infinite causal chain is its own cause.
Edward Feser argues that an essentially ordered series of causes cannot regress to infinity, even if it may be theoretically possible for accidentally ordered causes to do so. Severinsen argues that there is an "infinite" and complex causal structure. White tried to introduce an argument "without appeal to the principle of sufficient reason and without denying the possibility of an infinite causal regress". A number of other arguments have been offered to demonstrate that an actual infinite regress cannot exist, viz. the argument for the impossibility of concrete actual infinities, the argument for the impossibility of traversing an actual infinite, the argument from the lack of capacity to begin to exist, and various arguments from paradoxes.
