Recent years have seen an emerging interest in introducing Islamic concepts and approaches to the analytic philosophy of religion. Mohammad Saleh Zarepour's recent Element is a welcome addition to this novel project. In this book, Zarepour reconstructs six arguments for the existence and unity of God originating from Avicenna's writings. The first four arguments are different interpretations of the Proof of the Sincere (Burhān al-Ṣiddīqīn) – Avicenna's a priori argument(s) for the existence of a necessary being. The last two arguments, furthermore, are for the singularity and simplicity of the necessary being whose existence has been defended in the first four arguments. The six arguments are preceded by a short summary of the ontological framework espoused by Avicenna and assumed throughout the arguments.
In constructing the theoretical framework, Zarepour begins by demonstrating that, like Anselm, Avicenna defends a single-divine-attribute doctrine in which he maintains that there is a single unique divine attribute from which all of God's other attributes can be derived. For Avicenna, though, this attribute is necessary existence. Furthermore, Zarepour introduces three ontological commitments held by Avicenna and presumed in the six arguments. First, the propositions ‘something exists’ and ‘there is existence’ are a priori facts entailed by the a priori proposition ‘I exist’. The a priori status of the proposition ‘I exist’ is supposed to be established by Avicenna's well-known thought experiment of ‘The Flying Man’. Second, any existing object is either a necessary being or a possible being which, although possible in itself, is necessitated by another being – its cause. From a reverse outlook, thus, Avicenna is of the view that every existent is either necessary in itself or necessary by something else. If the existent is uncaused then it is necessary by itself, and if it is caused, then it is necessary by its cause (i.e. if the cause were to exist, the caused object cannot not exist). Note that both merely possible objects and impossibilia are excluded from Avicenna's division, because he seems to be only concerned with existing objects. Third, generally speaking, Avicenna distinguishes essence from existence. The essence of an object is its definition or whatness, which is independent of whether or not that object exists. When it comes to the necessary being, however, His essence is identical to His existence according to Avicenna, because if His essence is distinct from His existence, then, with everything being equal, His essence would be neutral with regard to existence and non-existence. This means that in order for the necessary being's essence to exist, He needs something to tip the scale for existence over non-existence – namely, a cause. However, this means that the necessary being is caused and thus is not a necessary being that is by definition uncaused. Thus, assuming that the essence of the necessary being is not identical to His existence leads to a contradiction.
In a further addition to the theoretical framework of the arguments, Zarepour defends three metaphysical principles. The first is the Principle of Irreflexivity of Causation, which dictates that nothing, whether possible or necessary, is self-caused. The second is a weaker version of the Principle of Sufficient Reason, which states that every existent whose existence is not necessary must have a cause for its existence. The third is what Zarepour calls the Necessitation Principle, which, he argues, holds that if something is possible in itself, but necessitated by its cause, then there is a necessary being in its chain of past causes.
After laying down the theoretical framework, Zarepour embarks on the main arguments of his Element. The first four arguments are for the existence of a necessary being, the fifth is for the singularity of the necessary being, and the last argument is for the simplicity of the necessary being.
The first argument is meant to prove the existence of God merely from the fact that God is a necessary being. Zarepour provides two versions of the first argument. The first one is a reductio argument that aims to demonstrate that assuming the non-existence of God leads to a contradiction. It goes as follows. Given that, by definition, a necessary being cannot not exist, and that God is, by definition, a necessary being, God cannot not exist. From this conclusion and a reductio assumption that God does not exist, Zarepour derives a contradiction.
The second version of the first argument has some striking similarities with Alvin Plantinga's ontological argument. It goes as follows:
1. There can be a necessary being.
Therefore, there is a necessary being.
The rationale behind this argument is straightforward. If it is possible to have a necessary being who is uncaused and cannot not exist, then there is nothing to prevent this being from existing, but if that is so and the necessary being, by definition, cannot not exist, then a necessary being exists.
Zarepour then moves to his second Avicennian argument for the existence of a necessary being. It goes as follows:
1. There is an existent, call it X (assumption).
2. Any existent object is either necessary in itself or possible in itself, but necessitated by something else.
3. Hence, X is either necessary in itself or possible in itself, but necessitated by something else.
4. If X is necessary in itself then there exists a necessary being.
5. If X is possible in itself but necessitated by something else, then there must be a necessary being in X's chain of causes.
6. Hence, if X is possible in itself then a necessary being exists.
Therefore, a necessary being exists (from 3, 4 and 6).
The soundness of this argument depends on the soundness of the three metaphysical principles mentioned above: the weaker version of the Principle of Sufficient Reason, the Principle of Irreflexivity of Causation, and the Necessitation Principle.
The third argument presumes Avicenna's ontological stance on the impossibility of actual infinities, in addition to the other principles presumed in the first two arguments. It aims to establish that since it is impossible for any possible existent to have an infinite past linear causal chain and that it is impossible for it to have a past circular causal chain, it must have a linearly finite causal past. If it has a linearly finite past, however, then there exists a necessary being. The reason behind this is that the necessary being is the only being that does not need a cause for its existence, and, hence, any finite chain of causes needs such a being with which to begin the chain.
The fourth argument is Zarepour's restructuring of the better-known version of the Proof of the Sincere (Burhān al-Ṣiddīqīn). The argument goes as follows. If a possible existent exits, then the totality of possible existents exists. Moreover, the totality of possible existents is either necessary in itself or possible in itself. If it is necessary in itself, then a necessary being exists. If it is possible in itself, then there is a necessary being that causes it to be, because if its cause is not necessary in itself, then the cause will be part of the totality of possible existents. Hence the totality of possible existents would be the cause of itself, an outcome that Avicenna rejects. Thus, if a possible existent exists, a necessary being exists, and, clearly, there exists at least one possible existent.
Zarepour's different versions of the Proof of the Sincere (Burhān al-Ṣiddīqīn) establishes, if successful, only that there is at least one necessary being. Hence, Zarepour, on the basis of Avicenna's writings, reconstructs two further arguments: one for the unity of the necessary being and the other for His simplicity.
The argument for the unity of God goes as follows. The individuation of any necessary being either comes from His essence or, at least partly, from His accidents. It is impossible that the individuation of any necessary being be due to His accidents. Hence, His individuation must come from His essence. But if the individuation of one necessary being (call it G) comes only from His essence, then every necessary being having the same essence as G will be identical to G. Therefore, there is only one necessary being.
Zarepour then moves to the last argument in his Element in which he defends the simplicity of the necessary being. It goes as follows. If the necessary being is not simple, then it is a compound of at least two parts. These parts, even if they do not have temporal or causal priority over the whole, have at least some explanatory priority, at least according to Avicenna's metaphysics. But if that is the case, then the necessary being depends on something other than Himself (in this case His parts). This, however, means that He will cease to be a necessary being who by definition is totally self-dependent. This leads to a contradiction – that the necessary being is not a necessary being. This argument concludes the six interesting arguments that Zarepour tackles in his book.
It is important to register a point of appreciation for the fact that Zarepour's Element is not merely a commentary of Avicenna's philosophy. The author's original contribution to the arguments and their theoretical background is most obvious. Indeed, the author himself acknowledges this feature of the book. He states:
It must be emphasised that my primary concern in the following discussion is the philosophical strength of the arguments I offer, rather than historical accuracy and textual fidelity. So although the kernels of all arguments are extracted from Avicenna’s texts, I do not hesitate to compromise on certain details . . . where this might make my arguments more coherent and compelling for a contemporary reader. (p. 6)
Personal original contribution is a distinctive feature of most analytic philosophy and is unfortunately missing from many recent attempts of practising Islamic analytic philosophers. Fortunately, this book does not fall short when it comes to reflecting this or indeed many other features of analytic philosophy. Notwithstanding, I would have preferred it if Zarepour were even less reliant on Avicenna's philosophy. I wished to see Avicenna as more of an inspirational figure to Zarepour rather than an authority – something like the presence of John Calvin, for instance, in parts of Alvin Plantinga's philosophy. This is a minor quibble though, as the book is indeed excellent, well-written, and a must-read for anyone interested in the emerging branch of Islamic analytic philosophy.
