Al-Attas' Prolegomena to the Metaphysics of Islam contained a number of monographs, which for me arranged in a beautifully crafted sequence in order to prepare its reader for the complexity of its subject. The long Introduction and the first 2 chapters are dedicated to outline the general limits and contents of Islamic metaphysics. A metaphor would be akin to the "negative" attributes of God (as-sifat al-salbiyah), which function to deny God from things or attributes that are impossible for Him, rather than prescribing a positive and substantive explicative of His Most Exalted Essence. The first part of the Prolegomena is essential because it showcased the fastidiousness of al-Attas in embracing the rightful creed of Islam, to emphasize on the transcendence and exaltedness of God, free from any form of incarnation or union.
The rest of the book focused on the expounding on the doctrine of the primacy of existence. In my opinion, this book is ultimately a work outlining the aforesaid doctrine, or the more notoriously known as the Unity of Existence (wahdah al-Wujud). One can easily get perplexed, or perhaps annoyed, on the complexity of this doctrine. But as al-Attas hinted in the title, ontology as understood by the metaphysicians stand in stark contrast against what the theologians and the philosophers believed in. al-Attas strived to show the context on how this entire doctrine is basically a synthesis, the only correct synthesis and framework in understanding Reality. To understand the context, we must then rummaged through the debacle between the philosophers, theologians and metaphysicians.
The philosophers and the theologians, ignoring their many other differences, commonly believed that while existence is a general concept underlying all existents, it is only accidental to quiddities and essences. What this means is that existence is an attribute superadded into the mind only after the thing is being cognized in the mind. Essence, instead of existence has the ontological priority of everything existing. The metaphysicians, on the other hand, believed that it was existence that possesses the ontological priority. This is because what the philosophers and the theologians belief amounts to is that God who is the Absolute Existence does not possess any extramental existence, simply because they believed that existence is a mental idea/concept. This is impossible and absurd, because God's Existence is absolute and real; it underlies the reality of everything existents. Thus the context for the primacy of existence as expounded throughout this book. Please be reminded that this is an extreme simplification of the arguments brought by al-Attas.
Next, because God's existence is Absolute, this implies un-limitedness and unboundedness. Absolute means as it is, God's existence occupies everything and underlies everything. God's Existence is real. If we are to imply there's another substance that exists in a real way as God's Existence, then we unavoidably saying that there's a partner in God's Absolute Existence, and that God's Absoluteness in Existence possess a limit and boundary next to this substance existence, which is absurd. Thus, the metaphysicians believed that the only way to preserve God's Unity is to prescribe the all-encompassing Existence in explaining the Reality of all things. Thus there is only One Real existence, what is other than God their existence are conditional, limited and metaphorical. Here is the oversimplified context for the doctrine of Unity of Existence.
A very jarring question for this is that, if there's only one existence, then does everything existents partakes of God's Essence? At this level, there would be knee-jerk reflex of saying that this ideology is fallacious because it is saying that God is imminent in the world, that even Hitler or cow's dropping is God if we are to prescribe this doctrine. A simple answer to this question is a firm no. A more elaborate explanation could be found below, but here's a succinct parable presented by al-Raniri, perhaps modified from al-Ghazzali's Niche of Light. The existence of the image in the mirror is not independent at all, in terms that it requires the presence of the Gazer for it to manifest itself. And it is indeed foolish to say that the image and the Gazer possessed any kind of similarity in essence, because there's simply none; just like the luminosity of the Sun never decrease when it lighten up the World. So it is clear that the existence of the image is conditional, limited and posterior to the presence of the Gazer, it does not possess any substantial existence prior the determination from the Gazer, nor does it partakes anything from the Gazer's essence.
Thus, because this doctrine is the inevitable way that simultaneously preserve the Unity and transcendence of God, and also bypass the jettison of multiplicity of existence, al-Attas believed that this is the rightful ontological creed in Islam, as affirmed by many great metaphysicians. Now moving on the main body of the monographs.
We have briefly mentioned that Absolute Existence belongs to God, and God only. But we also have cognized the multiplicity of existence, which we rightly denied to be partaken by any how and way with God's Essence? How can it be possible, for the One to become Many? al-Attas answered that this one Existence possessed multiple layers of existence; layers of self-manifestations. From absolutely undetermined and unlimitedness to the determined and the limitedness of everything existence. But keep in mind these 2 things: these stages of existence do not occur in sequence i.e temporally. Existence as we know it as the multiplicity of things, as we shall see later, is a dynamic process and continuous in nature, appropriate with its status as the created, or more accurately the "ever-new".
Observe this: everybody readily affirm that everything created possess a beginning and an end, but how in between the beginning and the end? Is it possible to conceive the things as to be enduring and persists even between two infinitesimal points of duration? If it is, does it not make itself a contestant for God's absolute persistence and enduring in existing, which is absurd? Thus, the created does not simply possess a beginning and the end, it is ever-created, its existence is conditional, caused and needy for the Power that continually renew it.
Thus the process of existence occurs dynamically, perpetually and simultaneously. Secondly, we must get rid of any notion imagining the ontological "descent" of the Absolute Existence from being undetermined to determined to happen in space or in any kind of form. Language does not conjure the reality of a thing; it rather points towards a thing. Language as described by the metaphysicians acts as the vehicle for us to gain understanding, not its reality.
Now we shall begin to outline the degrees of existence, as thought by the metaphysicians. God in the first stage of existence, stand in its Absolute Oneness. His Essence would be forever be locked, forever be unknown as it simply escaped any limitations and determinations, two functions of our mind capable of. But God contemplates in His Perfection, and raises a mirror to manifest His Essential Perfections, giving rise to exterior, self-revealing aspect of Himself. The hidden, interior aspect of His Essence is known as ahadiyyah mutlaq, and the exterior, self-revealing aspect al-wujud mutlaq. At the stage of al-wujud al-mutlaq, it is already pregnant with infinite possibilities of determination in a state of unlimitedness. It does not involved in any determination, but ready to manifest itself in determination. al-Wujud al-Mutlaq itself is the interior/hidden aspect of the second stage of existence: wujud al-amm.
In the second stage of general existence, there arises a pair of opposites: between the active, necessary and divine manifestations with the passive, contingent and creaturely manifestations. This stage is also known as Divine Unity, where everything is still being indeterminate, but now free to engage in the next stages of determination.
The third stage would be the the stage of Divinity, or Divine Attributes. Here the active, necessary and divine manifestations are further determined to form the Divine Attributes of God. Only at this stage the Essence can be cognised as God, as now He reveals Himself via His Names and Attributes.
The fourth degree of existence would be the Permanent Archetypes, where ideas of intelligibles exists eternally in the Divine Knowledge. These are the original realities of things whose future states are to be actualized at the lower degrees of ontological level. Now we have seen the increasingly determinate existence into Divine Names and Attributes and now Permanent Archetypes. These two prepared the locus of manifestation of things in the lower degrees, more or less serving as a mirror where light can be reflected. The mirror is not the possessor of the thing i.e. the thing is not in the mirror, only its form. This is important as this serves the re-emphasize the Divine Unity and transcendence of God.
The fifth degree of existence involved the Exterior Archetypes, which acts as the active evolvers of actualizations inherent in the permanent archetypes, in accordance with the requirements of all their future states. Thus each degree of existence serves as a more determinate locus for things to be manifested in its multiplicity, a Many from a Unity. And the sixth degree would be the empirical world as cognized by all of us.
A metaphor describing this entire ontological descent of Divine Essence is that God wished (again a metaphor) to see himself in the mirror to behold His Resplendent Beauty and beheld the miraculous mirror, which reflected His Essential Perfections, His Divine Attributes. By the virtue of His Infinite Names and Attributes, each reflecting a different aspect of His Being, producing a variegated multiplicity of images without impairing the Absolute Oneness of His Being. Each mirrors reflecting different aspect of His Names. It reflected the form not the essence of the beholder. What appear is in accordance with the nature of that essence according to the form that holds it, but not the Truth as He is in His Absoluteness. The nature of the locus/mirror itself provides the limit to the inherent potentiality of the images that would appear in it. He is, at the end, the One Substance; the rest of the manifestations are merely accidents to Him.
A second metaphor would be that the person who casts a shadow is the only one that is Real. The locus where the shadow is cast stand as the permanent archetype, a theatre for manifestations. The Light by virtue the shadow can be made manifest is the Divine Names, not the Essence. The shadows thus, are mere potentialities having no actual existence. It requires perpetually for the shadow, thus its existence is only possible, not actual.
Now we have delineate the degrees of existence, what is then the position of the world? Does everything is an illusion? Is a shadow an illusion just because its existence is conditional? Definitely not! A more apt term describing the existence of the external world would be metaphorical in existence. The word majaz describes about something allowable, something passable. Thus the world is metaphorical in existence in the sense that it allows the transfer of meaning of existence from something eternal and self-subsistent (the Divine Essence) to something non-eternal (the world) via the connection between the two senses of meaning. Consider on how the courageous man could be described as a lion because of the existence of connection of meaning between the two. The world thus, does not possess real existence, but appear to be so due to its apparent continuity. But as we explained before, the created existence is discontinuous and in perpetual dynamic, only to be considered as existing as long as it is related to the Absolute Existence.
I believed that I have outlined the monograph as best as I can. The doctrine of primacy of existence is sound as explicated by al-Attas. It serves to preserve the Unity of God par excellence and solved the eternal debacle between essence and quiddity, unity and multiplicity, eternity and temporality.