The Problem of Causality in the Kalām Argument
The two most common objections raised against the Kalām version of the Cosmological Argument fail to undermine its central premises and therefore God likely exists.
The Kalām Argument for the existence of God is based upon two premises that have been often challenged and which are still debated to this day: (1) that everything that begins to exist has a cause and (2) that the universe began to exist. In this post, I examine one philosophical objection to each of these premises and the responses given by supporters of the Kalām Argument. For the major (first) premise, I look at the objection that it is not deductively certain that everything that comes to exist has a cause. For the minor premise, I consider the objection that mathematics has shown that an infinite set can exist in the real world and that, therefore, the universe could simply have no beginning. I argue that these objections fail to undermine the logical intuitions at the heart of each premise and that, therefore, the Kalām Argument remains a sound argument for the existence of God. For the purposes of this post, “God” is understood as the transcendent and eternal cause of all that exists in the universe, and a sound inductive argument is one in which, if the statements (premises) upon which it is based are likely true, the conclusion is also likely true.
I. The Kalām Argument
According to the Kalām Argument’s most famous contemporary defender, William Craig, the argument arose out of attempts by early Christian theologians to defend the Biblical teaching of creatio ex nihilo against classical Greek notions that the universe has simply always existed (Craig, 2012: 101). This effort was taken up by medieval Islamic theologians, particularly Al-Ghazali in his book The Incoherence of the Philosophers, in which they argued that the universe must have a beginning and that therefore a Creator brought it into existence. As Al-Ghazali put it, “[e]very being which begins has a cause for its beginning; now the world is a being which begins; therefore, it possesses a cause for its beginning (cited by Craig, 2012, 96).” The argument is elegant in its sheer simplicity:
P1. If something begins to exist, it has a cause.
P2. The universe began to exist.
C1. Therefore, the universe has a cause.
II. Objection to the Major Premise: Not Deductively Certain
The popularity of the Kalām Argument may be due to the apparent strength of its two premises. That everything that begins to exist has a cause seems to many people, if not to all philosophers, to be self-evident. It has been variously viewed as an inductive generalization based on empirical observation or, alternatively, as a self-evident principle of intelligibility like the Principle of Non-Contradiction (Melamed & Lin, 2021). Another, more recent name for this premise is the Principle of Sufficient Reason (PSR), formulated by Gottfried Leibnitz, which asserts that “everything must have a reason, cause, or ground (Melamed and Lin, 2021).” In his Dialogues on Natural Religion, David Hume summed up the principle this way: “Whatever exists must have a cause or reason of its existence; it being absolutely impossible for any thing to produce itself, or to be the cause of its own existence. (Hume, 1990: 98).
However, it sometimes comes as a shock to students of philosophy that not all philosophers accept the PSR as self-evident. Various philosophers have raised objections to the assumption that everything must have a cause or reason for its existence. According to Hume himself in the Treatise, there are at least three reasons why it is neither intuitively nor demonstrably certain that “whatever begins to exist, must have a cause of existence (Hume, 2014: 56).” First, Hume says, it is possible to imagine something beginning to exist without a cause and if something is conceivable and not in itself self-contradictory, then it must be at least theoretically possible (Hume, 2014: 56). The second reason why the premise is not certain, according to Hume, is because the argument is fallacious that asserts if something exists without a cause then it must have caused itself. This argument, Hume claims, simply begs the question, since it assumes rather than proves that everything must have a cause, whether of itself or by another (Hume, 2014: 57). The third reason Hume gives for why it is not certain that everything that begins to exist has a cause is because you do not have to assert that nothing caused something to exist, which is, he concedes, impossible. Rather, you can simply say that something exists and neither nothing nor itself caused it to exist (Hume, 2014: 57).
In response, I would argue that Hume is not objecting to the premise itself but only to the claim that the premise can be shown to be intuitively or demonstrably certain. Hume himself strenuously denied that things can begin to exist without a cause precisely because there is no evidence of such a thing in experience. In fact, he called such a belief “absurd.” “But allow me to tell you that I never asserted so absurd a Proposition as that anything might arise without a cause,” the philosopher wrote to a friend in 1754. “I only maintain’d, that our Certainty of the Falsehood of that Proposition proceeded neither from Intuition nor Demonstration, but from another source (Letters, cited by Craig, 2008: 113).” That other source is “observation and experience” or induction (Hume, 2014: 57). Hume thus accepts the truth of the major premise in the Kalām Argument but insists that it is not a certain truth, known a priori, but only a probable truth known from experience. In other words, those who object to the first premise of the Kalām Argument by appealing to Hume’s distinction between certain a priori knowledge and merely probable experience do not really make their case. Hume himself denied, rather than affirmed, that anything might arise without a cause. Whether we know this deductively a priori or inductively from experience does not change the fact that everything that begins to exist has a cause.
In addition, recently Alexander Pruss and Robert Koons have argued that if the PSR is not true – that is, if events can occur without causes – then we can never be sure of any extra-mental facts. We must arrive at an extreme solipsism as the only viable philosophical outlook. “If the PSR is false in epistemically relevant scenarios, then there are relevant scenarios in which our condition is just as bad as they are for Descartes’s hypothetical victim [of an evil illusion-making demon] – in which we have empirical data, but the data is not caused in the right way to provide empirical knowledge, because the data is not caused at all but has simply ‘popped’ into existence without any cause at all,” they write (Koons & Pruss, 2020: 1085). The authors restrict the PSR to “natural facts” because they argue that the PSR requires that at least one supernatural fact is true, that is, that a necessary being exists that explains the existence of all other beings (Koons & Pruss, 2020: 1080).
We have just looked at one common objection to the Kalām Argument’s major premise, that everything that begins to exist must have a cause. I have shown that, while the objection that the premise is not deductively certain has merit, it does not suffice to undermine its truth -- not least because to deny it would be to deny the possibility of all knowledge.
We will now look briefly at one common objection to the minor premise in the Kalām Argument, that the universe began to exist.
III. Objection to the Minor Premise: Infinite Sets
A common objection to the minor premise is that mathematics has demonstrated that infinite sets are possible and that therefore an infinite regress of past events and a universe without beginning are possible. In the history of philosophy, this is a relatively new objection. Since at least the time of Aristotle, philosophers have argued that an infinite regress of causes is absurd because it would mean that some initial events in the chain would occur without a cause. To use a metaphor made famous by Bertrand Russell, if you claim the earth doesn’t fall in space because it rests on the back of a turtle, you must also explain why the turtle doesn’t fall – and, if it’s “turtles all the way down,” as one of Russell’s listeners put it, you must explain why the pillar of turtles doesn’t fall (Pruss, 2018: 27). In other words, while it may be possible to imagine a potentially infinite number of causes mentally, the existence of an infinite set of any objects in the real universe – or an infinite chain of causes – would lead to self-contradictory absurdities (Craig and Sinclair, 2012: 109).
Prior to the 19th century, many philosophers and mathematicians believed that the concept of infinity, while valid in mathematics, was not applicable to the real universe. Some realities, such as the future, could be potentially infinite but not actually infinite. But in the late 19th century, the German mathematician Georg Cantor invented a new branch of mathematics known as set theory that allegedly proved that an infinite set is possible in the real world, not just in the purely mental world of mathematics. This led to apparent paradoxes. For example, according to Cantor if you double the size of an infinite set of natural numbers (1, 2, 3, 4...) it is no larger in size than the original set. Both are infinite. In fact, if you multiply such a set by any number n the result is no larger than the original set (Nagasawa, 2011: 114).
However true this may be in mathematics, it begs the question of whether such paradoxical marvels can and do exist in the physical world. Even such a strong defender of Cantor’s set theory as the mathematician David Hilbert declared that “[t]he infinite is nowhere to be found in reality” (cited in Craig and Sinclair, 2012: 107). For his part, Craig seeks to demonstrate this with thought experiments such as Hilbert’s Hotel. The thought experiment goes like this. If a new guest shows up to a hotel that has an infinite number of occupied rooms, all the hotel must do to accommodate the new arrival is to move the guest in Room #1 into Room #2, the guest in Room #2 into Room #3, and so on, and then there is room for one more in Room #1. Yet the same thing can be done with an infinite number of new arrivals, leading to the logical absurdity of an infinite number of occupied rooms in a hotel that can accommodate an infinite number of new arrivals (Craig and Sinclair, 2009: 105-6).
Not all philosophers find such thought experiments persuasive or relevant to the question of whether the universe could have no beginning (Oppy, 2009: 140). Nevertheless, I would argue that thought experiments such as these do suggest that infinite sets violate the Euclidean maxim and logical intuition that wholes are greater than their parts (Zarepour, 2021: 474) and therefore show, as Craig and Sinclair put it, that “an actual infinite cannot exist in the real world” (Craig and Sinclair, 2012: 106). To claim that the set of all books in a library with infinite books is no larger than just the books with titles beginning with the letter Z violates this basic logical intuition of wholes being greater than parts (Nagasawa, 2011: 134). Of course, a common response to this reasoning is that infinite multitudes plainly do exist in the real world because every spatial or temporal interval is divisible into an infinite number of sub-segments (Oppy, 2009: 140). In fact, one philosopher even asserts that actual infinities “abound in the physical world” because every time you wave your hand it passes through “an infinite number of intervening segments” (Zarepour, 2021: 476). However, it is by no means clear that a line or an interval of time consists of an infinite number of segments in the real world. Both the universe and time are continuous wholes that can be divided up into infinite parts in our minds but not in reality (Craig and Sinclair, 2009: 112-113).
IV. Conclusion
In this paper, I have argued that that the objection often raised against the first premise of the Kalām Argument – that is, that it is not deductively certain that everything that begins to exist must have a cause – fails to undermine the truth of the premise in any significant way. This objection merely shows, as Hume himself was forced to concede, that the truth of universal causation is not known a priori but only from experience. I have also argued that those who claim mathematics has shown that an infinite past with no beginning is plausible have, in fact, done no such thing. The set theory upon which this objection is based remains controversial even among mathematicians and, I argue, results in logical absurdities that violate basic intuitions about wholes being greater than parts (Zarepour, 2021: 474). I therefore conclude that both premises of the Kalām Argument are likely true, despite these two objections, and that therefore the universe does have an ultimate or first cause for its existence. That this cause is an entity of infinite power and intelligence, and possibly beneficent, is beyond the scope of the Kalām Argument and, therefore, this paper.
Works Cited
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