Apr 28, 2017
The notion that effects follow causes is fundamental to how we understand and experience the world. We conduct our lives, explain present events, and anticipate future events, without ever doubting cause and effect. Moreover, without their inseparability, neither could there be moral responsibility nor could we establish laws or pursue scientific inquiries. In short, every interaction humans have with the things and events around them is based upon the belief that, at minimum, there is some form of regular connection between causes and effects; otherwise, our perceptions and our knowledge of the world would become impossibly discordant.
This seemingly uncontroversial notion, however, has been the subject of extensive exploration by philosophers of all faiths since the ancient period. A crucial difference represented by two Muslim scholars—the philosopher Avicenna (d. 1037) and the theologian Abū Ĥāmid al-Ghazālī (d. 1111)—reveals how the concerns of theology can challenge and even shape our understanding of something as elemental as cause and effect.
Avicenna, the philosopher, never questioned the connection of causes to effects, or what is called causality in philosophical discussions. He also did not deny that things occurring in nature are endowed with powers that make them efficient causes—that is to say, agents inherently capable of producing their effects. For Avicenna, water itself is what makes something wet. Finally, he viewed the connection between a cause and its effect as that of necessity: if a cause exists, its effect necessarily follows.
But al-Ghazālī rejects Avicenna’s theory of causality—the notion that causes themselves produce effects—because he views it as incompatible with the belief that God is the only true cause.1 He also sees that affirming the connection between cause and effect led philosophers such as Avicenna to reject the possibility of certain miracles that, by definition, break the causal relationship of events in nature. Instead, al-Ghazālī argues that what we perceive as causes and effects are ordained by God not to be connected but only to be associated with each other in the course of events. Here, he succeeds in providing an argument for the possibility of miracles because effects now depend only upon God’s will, not upon apparent causes.
Al-Ghazālī’s solution, however, is not without its own difficulties; namely, it raises doubt about our perception of the apparent uniform course of events. Without cause and effect, what reason is there to believe that anything about our world is predictable?
In The Incoherence of the Philosophers (Tahāfut al-falāsifah), al-Ghazālī presented his most comprehensive discussion of causality; though this did not attract the attention of some Muslim theologians or philosophers after him for some time, contemporary scholars have given al-Ghazālī’s discussion renewed focus, something that can be explained by the rising popularity of the connection between cause and effect in philosophical discussions after it became the object of a serious attack by the Scottish empiricist David Hume (d. 1776) and because al-Ghazālī is the only Muslim theologian who provided theological and philosophical arguments in his rejection of the necessity of causes. Al-Ghazālī wrote The Incoherence to defend Ash¢arī theology, an orthodox school in Sunni Islam, and to show how the philosophers (mainly Avicenna)2 deviated from many core Islamic beliefs, such as their denial of the possibility of miracles that violate the course of natural events.
Avicenna, meanwhile, based his understanding of causality on Aristotle’s theory of the four causes: material, formal, efficient, and final.3 What concerns us here is his view about natural efficient causes—that if a natural cause exists, its effect necessarily follows. Avicenna distinguishes between natural efficient causes and metaphysical efficient causes. The first are things in nature that cause changes in other things in nature, while a metaphysical cause—such as God—gives existence. “When philosophers discuss the efficient cause, they do not mean by ‘agent’ (fā¢il) only the principle of motion (change), as the naturalists mean, but the principle and giver of existence, as in the case of God with respect to the world.”4 As for the conditions that determine the connection between a natural cause and its effect, Avicenna explains that “the existence of the effect (al-ma¢lūl) depends on the cause insofar as the cause is in a condition that makes it a cause either by nature or by will or something else that is needed from outside that has an influence in completing the cause and making it a cause in actuality,” and when “the required condition exists, then it is necessary that the effect exists.”5
It is clear, then, that Avicenna views the nature of the relationship between natural causes and their effects in the light of the nature of objects, through which they either become active causes or recipients of the effect of causes. Natural causes, however, are always conditioned by their internal natures and by external factors, which are equally important in order for a cause to be a complete cause. Hence, when the cause actually exists with all the required internal and external conditions, its effect necessarily follows; otherwise, denying that the cause necessitates its effects is a contradiction because it amounts to denying its very nature. For example, that fire has an active power to burn and that cotton has the nature to be burned are both internal conditions. If an external condition is also met—for example, by fire coming into contact with cotton without any impediments, such as something that makes the cotton wet—then burning would necessarily follow.6
In The Incoherence, al-Ghazālī rejects Avicenna’s theory about natural causes because he considers it to be incompatible with God’s omnipotence and also because it implies the impossibility of miracles that upend natural order. Al-Ghazālī affirms that many conclusions and ideas of the Muslim philosophers (i.e., Avicenna) concerning physics do not contradict religion, but he asserts that four of their metaphysical claims in physics must be rejected. The first of these is about causality; he writes, “Their judgment that this connection between causes and effects that one observes in existence is a connection of necessary concomitance, so that it is within neither [the realm of] power nor within [that of] possibility to bring about the cause without the effect or the effect without the cause.”7
Al-Ghazālī’s rejection of this claim is motivated by the assumption that believing in the necessary connection between natural causes and effects would suggest that the presumed necessity makes it impossible, even for God, to bring about an effect without the existence of its own specific cause. This would contradict the belief in an omnipotent God. But al-Ghazālī mainly wants to prove that certain types of miracles described in the Qur’an are possible. According to al-Ghazālī, Avicenna rejects miracles such as “changing of the staff into a serpent, the revivification of the dead, and other [miracles of the kind]. For this reason it becomes necessary to plunge into this question to affirm miracles and [to achieve] something else—namely, to support what all Muslims agree on, to the effect that God has power over all things.”8
Al-Ghazālī thus starts his discussion about the nature of causality by affirming that “the connection between what is usually believed to be a cause and what is believed to be an effect is not necessary.”9 In this view, things by their nature have absolute independence from each other, and the belief that different things are bound to each other through necessary connection is no longer sustainable. Therefore, for any two different things, “it is not a necessity of the existence of the one that the other should exist, and it is not a necessity of the nonexistence of the one that the other should not exist.”10 Al-Ghazālī presents a few examples, such as “the quenching of thirst and drinking, satiety and eating, burning and contact with fire, light and the appearance of the sun, death and decapitation, healing and the drinking of medicine” and concludes these include all that is “observable among connected things in medicine, astronomy, arts, and crafts.”10 The events described in these examples do not reflect the nature of the objects involved nor do they indicate that there is a necessary connection between them.
Why, then, do things occur in a certain sequence and constant pattern, despite the fact that nothing in their nature dictates such a pattern? According to al-Ghazālī, “Their association is due to the prior decree of God, who creates them side by side, not to its being necessary in itself, incapable of separation.”11 And, because there is no necessary connection between them, it is possible that God “creates satiety without eating, and … continues life after decapitation, and so to all other things.”10
In The Incoherence and The Scale of Knowledge, al-Ghazālī neglects discussing the widely accepted belief among Muslim theologians and philosophers that the concept that every effect must have a cause is self-evident. Neither does he present an account of the nature of the connection between objects, other than describing things as co-existents. Rather, he focuses on refuting Avicenna’s claim of the necessary connection between natural causes and their effects. But in The Median in Belief (al-Iqtiśād fī al-i¢tiqād), which is an essential theological work he wrote after The Incoherence, he presents the following argument for the existence of God: “Every originated thing (ĥādith) must have a cause for its origination, and the world is an originated thing, therefore, it necessarily must have a cause.”25 It is clear that the validity of this argument depends on the truth of the first premise; namely, “every originated thing must have a cause.” According to al-Ghazālī, “this principle must be affirmed since it is a self-evident (awwalī) and necessary (đarūrī) principle according to reason.”26
This argument elicits an immediate question: Is it possible to affirm that it is necessary that for every event, or originated thing, there must be a cause, while at the same time denying there is causal connection between natural objects? Although al-Ghazālī did not address this self-evident question in his discussion of causality, one can surmise that al-Ghazālī might argue that, because God is the only true cause, the notion of causality is true only for God. In other words, the phenomenon of cause and effect exists, but there is only one cause: God. But this answer means that al-Ghazālī would not believe that denying natural causality while affirming a necessary cause for every originated thing is a contradiction. On the surface, however, this apparent contradiction causes a tension in al-Ghazālī’s view of causality that he ideally should have addressed. Despite this tension, al-Ghazālī’s main objective behind his discussion of causality is to provide a rational explanation of the miracles mentioned in the Qur’an. To this effect, he made it clear that miracles are possible, whether we believe that natural events follow a course that is determined by the very nature of objects or we believe that God is the sole immediate cause of all events and that natural objects are devoid of efficacy. He also affirms that the denial of causality would not cause us to doubt our knowledge of the world. According to al-Ghazālī, our practical commitment about the course of events and the connection between natural objects is based on our natural inclination and reasoning, which play a valuable and essential role in removing doubt about the regularity of natural event.