By Zia H Shah MD, Chief Editor of the Muslim Times

The Many Worlds Interpretation (MWI) of quantum mechanics posits that the wavefunction of the entire universe is real and never collapses. Instead, whenever a quantum event has multiple possible outcomes, all outcomes occur, each in its own “branch” of reality. In this view, the universe continually splits into parallel, non-interacting worlds for every quantum measurement or observation. Time can thus be envisioned as a many-branched tree in which every possible outcome is realized in some branch. Crucially, this removes the randomness of a single outcome – every outcome happens in some world – and avoids the need for a mysterious wavefunction collapse.

Quantum decoherence plays a key role in modern MWI. Decoherence is the process by which quantum superpositions “branch” into apparent classical outcomes due to interactions with the environment. Once a quantum system becomes entangled with its environment, the different outcome states lose coherence with each other (their wavelike phases scramble) and no longer interfere. Effectively, the universe’s wavefunction decomposes into independent, non-communicating branches, each of which looks like a classically definite world. In other words, the appearance of a single outcome in each experiment is explained by decoherence causing the other possibilities to split off into separate worldsen.wikipedia.org. This continuous branching happens at countless events, yielding an enormous (ever-growing) number of parallel worlds existing simultaneouslyen.wikipedia.org.

Under MWI, the evolution of reality is fully deterministic and local. The universal wavefunction obeys the Schrödinger equation at all times, so nothing truly “random” occurs at a fundamental level – apparent randomness is just our uncertainty about which branch we occupy. The observer is also described by the wavefunction; when you perform a measurement, you split into multiple versions, each registering a different outcome. Each version of you perceives a definite result and a consistent history thereafter, unaware of the other branches. Thus, MWI asserts that we live in a vast multiverse: “a near-infinity of universes, all superimposed in the same physical space but mutually isolated and evolving independently,” containing countless versions of ourselves living out different possibilitiesquantamagazine.org. Though striking and counter-intuitive, this interpretation is taken seriously by many physicists and philosophers as a solution to quantum theory’s puzzles. It preserves quantum theory’s equations literally, at the cost of accepting that “the world turns out to be rather larger than we had anticipated” – our familiar world is only a small part of a much larger quantum reality theo-puzzles.ac.uk.

al-Ghazali’s Occasionalism: God as the Only True Cause

Turning from modern physics to medieval philosophy, Abu Hamid al-Ghazālī (1058–1111) put forward a doctrine known as occasionalism, centered on divine causation. Al-Ghazali denied that natural objects or events have any intrinsic causal power. In his view, God is the only genuine cause of every event in the worldplato.stanford.eduplato.stanford.edu. What we observe as “cause and effect” in nature is merely the habitual sequence of events that God directly orchestrates moment by moment. Several key ideas capture al-Ghazali’s occasionalism:

• God as Sole Actor: No created thing can produce effects by itself; every effect is directly caused by God’s will and powervlatkovedral.com. Creatures and natural forces are at best occasions for God’s action, not independent actorsplato.stanford.edu.
• Apparent Causation as Habit: The regularities of nature (like fire burning cotton or water quenching thirst) are constant conjunctions, not necessary linksbu.edu. We are used to seeing A followed by B, but it is not A that causes B – it is God causing B in the presence of Abu.edu.
• Contingency of Events: Because God is omnipotent and free, He could always will events to turn out differently. Al-Ghazali famously argued that if fire touches cotton, the cotton does not burn by the fire’s own nature – “fire does not burn cotton by its own power; rather, God causes the burning each time fire touches cotton.”thequran.lovethequran.love. God could prevent the cotton from burning or cause it to burn without fire. No physical cause necessitates its usual effect, since God could choose otherwise at any momentbu.edu.
• No Natural Necessity: Natural laws are not inviolable truths, but descriptions of God’s customary actionthequran.lovethequran.love. The sun rises each day or gravity pulls objects down only because God consistently wills these patterns. They have no independent efficacy apart from God’s continuous creation.
• Continuous Creation: Underlying this view is an atomistic cosmology: reality is re-created by God at each instant. “Every instant of the universe does not necessarily follow from the previous,” al-Ghazali held, “but is always – ab initio – created by God.”vlatkovedral.comvlatkovedral.com. The world persists from moment to moment only through God’s ongoing creative willsuhail-73754.medium.com. In a vivid image, the universe is like a flickering light being rekindled anew at each moment by the divine agent.

In sum, al-Ghazali’s doctrine abolishes natural causation: only divine volition links events. Fire, water, knives, or any purported “cause” have no inherent power to produce outcomes – God alone produces the effect on each occasionvlatkovedral.comvlatkovedral.com. This was a theological safeguard of God’s omnipotence and a rejection of the philosopher’s idea that causality resides in material natures. It emphasizes the absolute contingency of worldly events on God’s will. As al-Ghazali’s perspective suggests, the world could have been otherwise in any instance had God so willed; the causal order we observe is not logically necessary, but a result of constant divine choice.

MWI’s Philosophical Implications: Causality, Contingency, Determinism, Multiplicity

The Many Worlds Interpretation, though a physical theory, carries striking metaphysical implications that resonate with philosophical themes of causality and contingency. Key aspects include:

• Causality Without Unique Effects: In MWI, a given physical cause (like a quantum event) does not lead to one singular effect – it leads to all possible outcomes, each in a different world. This means the classical notion “same cause, same effect” no longer holds in a one-to-one way. Instead, the same cause yields a spectrum of effects across the multiverse. For an observer inside one world, it appears that one outcome happened and others didn’t; however, from the wider perspective of the universal wavefunction, every allowed outcome has occurred. This loosens the intuitive link between cause and effect. No particular result is mandatorily produced by prior events – other outcomes also happen (in other branches), so a cause does not necessitate one exclusive effect. In each individual branch the normal causal order applies (events follow from prior events consistently), but globally causation fans out into many parallel chains rather than a single sequenceen.wikipedia.orgen.wikipedia.org.
• Determinism and Lawfulness: Paradoxically, MWI is a completely deterministic framework at the fundamental level. The entire multiverse’s state evolves predictably by the Schrödinger equationen.wikipedia.org. There is no random collapse; nothing external “decides” outcomes. In this sense, the initial conditions and the laws of physics determine a unique multiverse. However, because that multiverse contains every outcome, observers within it experience what looks like randomness. Each branch feels an element of chance (“why did this outcome happen to me and not another?”), even though from the outside view all outcomes happen. This imbues MWI with a curious mix of global determinism and local indeterminism: the overall evolution is fixed, yet each individual world’s history feels contingent to its inhabitants. Notably, there is no violation of physical causality or conservation laws within any branch – each timeline is internally consistent and law-governeden.wikipedia.org. The difference is in multiplicity: causes lead to multiple effect-universes, not one.
• Contingency and Many Outcomes: MWI highlights a radical form of contingency in what we experience. Since every branching point realizes all possibilities, the particular way events turn out in our world was not the only way they could have turned out – and indeed in other worlds they turned out differently. For any event that happens (say, a particle decays at time $t$ or a cat survives in Schrödinger’s thought experiment), there are other branches where a different outcome occurred. This means that from the standpoint of any single world, there is nothing inevitable about its sequence of events; each event was one contingent possibility among many. The laws of quantum mechanics allowed various outcomes, and in the multiverse all those outcomes exist. Thus, our world’s history is one contingent path among a vast ensemble of alternative histories. In a way, MWI makes the contingency of outcomes very concrete: what “could have happened” does happen – just not in the world we inhabit.
• Metaphysical Multiplicity: Perhaps the most striking implication is the ontological plurality MWI introduces. Reality is not a single, unified cosmos with one history, but an immense plurality of coexisting worlds. These worlds are “parallel” in that they do not interact once separated (decoherence ensures they cannot affect each otherquantamagazine.org), but they are just as real as our own. MWI suggests a vision of existence that is much larger and richer than commonsense would indicate, containing what amounts to a vast collection of universes. In many of these universes there are versions of each person and object, “all but indistinguishable yet leading other lives,” as one science writer vividly puts itquantamagazine.org. This raises deep questions: what does it mean for something to be actual when countless alternate actualities also exist? The metaphysical picture is one of plentitude – a cosmos where every quantum possibility is realized. This multiplicity challenges us to rethink uniqueness and identity (each copy of “you” in each branch thinks it’s the real you). It’s a radical departure from the singular universe of classical thought, and it stretches concepts of reality to include a proliferating tree of worlds.

In summary, MWI forces us to confront a world in which causality is no longer one cause → one effect but one cause → many effects, determinism operates at the total level even as individual outcomes appear contingent, and reality itself is a multiplicity of branches. These features have interesting parallels (and contrasts) with al-Ghazali’s philosophical theology, especially concerning causation and contingency, as we explore next.

Bridging MWI and Occasionalism: Divine Freedom and Many Worlds

At first glance, MWI’s quantum multiverse and al-Ghazali’s occasionalist theology seem worlds apart – one is a physical interpretation without any mention of God, the other a medieval religious doctrine. Yet conceptually, both challenge the notion of a fixed, self-sufficient chain of natural causation, and both assert a kind of openness or multiplicity in how events come about. By examining these parallels, we can build a conceptual bridge between MWI and al-Ghazali’s thought:

• Undermining “Necessary” Causation: Al-Ghazali argued that observing A followed by B doesn’t prove A causes B necessarily – God produces B and could do otherwisebu.edubu.edu. Likewise, in MWI, a given prior state doesn’t produce one predetermined effect – it produces multiple outcomes. In both cases, the tight classical idea “given the cause, the effect must follow” is loosened. The connection between a prior state and a subsequent event is not one of absolute necessity. In occasionalism, that’s because God could will a different result; in MWI, it’s because quantum evolution leads to several results in parallel. Thus, both frameworks reject a singular necessary course of events. They emphasize that what happens need not have happened exactly that way – for al-Ghazali because God might have chosen differently, for MWI because another outcome does occur in a parallel world. Reality has a built-in contingency or flexibility at each juncture.
• Multiplicity of Possibilities: Occasionalism insists at any moment, many outcomes are possible since God is not constrained – e.g. a fire might burn or not burn a piece of cotton by God’s willbu.edu. MWI concretizes this idea: at each quantum event, every possible outcome is actualized in some branchen.wikipedia.org. One might say metaphorically that the multiverse “realizes” all the possibilities that al-Ghazali imagines God could choose from at each occasion. Instead of God selecting one path, the MWI multiverse encompasses all paths. This radical ontological plurality can be seen as analogous to God’s unrestricted freedom to create any outcome. Rather than God exercising choice to pick one possibility, the multiverse manifests divine plenitude by containing every possibility that the laws allow (if one were to interpret the multiverse theologically). In a sense, MWI’s picture of reality highlights the contingency of each world’s history: our world’s events were not the only possible ones – other worlds have different events. This resonates with the occasionalist view that nothing in nature compels one particular outcome; things happen the way they do because of a choice (in Ghazali’s view, a divine choice). MWI could be seen as illustrating that no single storyline has a monopoly on reality – a concept that philosophically bolsters the idea of contingency championed by al-Ghazali.
• Ultimate Agency and the Universal Wavefunction: In al-Ghazali’s framework, the ultimate agent behind all events is God. In MWI, there is no observer or agent causing branch splits – the process is automatic, governed by physics. However, one might draw an analogy by imagining the universal wavefunction (which governs all branches) as akin to a transcendent entity that encompasses all possibilities. Just as God’s knowledge in al-Ghazali’s view contains the entire plan of creation (every event in time, known timelessly)plato.stanford.eduplato.stanford.edu, the wavefunction’s evolution encodes all outcomes that will happen across the multiverse. We might say that from a “God’s-eye” perspective, the whole multiverse is a single deterministic creation, much like al-Ghazali’s God sustains a pre-planned cosmic orderplato.stanford.eduplato.stanford.edu. This is not to personify the wavefunction, but to note a structural similarity: One underlying reality gives rise to all observable events. In occasionalism it’s God’s continual creative will; in MWI it’s the unitary wavefunction dynamics. Both accounts imply that the surface level of events (what we see happening) is fully dependent on a deeper level (God’s will or the wavefunction) for its explanation. In that sense, the branches of the multiverse could be seen as analogous to the successive “occasions” of divine creation – each branch representing a complete sequence of events that unfolds according to underlying principles.
• Reimagining Divine Will in a Multiverse: If we take MWI as more than physics and use it metaphorically, we can explore a provocative theological idea: What if God actualizes not just one world history, but all possible world histories that are consistent with His laws? This is not al-Ghazali’s view, but it is a way to blend the concepts. Such a God would not be choosing one outcome to the exclusion of others; instead, every choice happens, and God’s will encompasses the entire branching structure. This could be seen as an ultimate expression of God’s creative freedom and abundance: no potential good or meaningful event He conceives goes un-realized, since every quantum possibility (perhaps corresponding to different courses of events) is given reality in some branch. In that scenario, our notion of divine volition would shift – God’s will would be expressed not in selecting one option at each event, but in establishing a reality where all options exist. Theologically, this is speculative, but it draws an analogy: MWI’s branching could reflect the idea of a God who is not constrained to a single world-line but generates a plenitude of worlds. It’s a way to think of divine creativity as infinitely prodigious, somewhat akin to God writing every possible story, rather than just one story. This might illuminate al-Ghazali’s emphasis on God’s unconstrained power: even though al-Ghazali himself said God’s plan produces one world, the MWI metaphor pushes us to imagine a multiverse as a canvas for God’s will.
• Metaphysical Contingency and Divine Sovereignty: Both MWI and occasionalism reinforce that what is (our experienced reality) rests on what could be otherwise. In al-Ghazali’s theology, the world’s continued existence and order are contingent on God’s continual choice – a supreme sovereignty where at any moment God could do something entirely different. In MWI, the existence of myriad alternative outcomes underscores that our world is not the only way things could have gone. This can serve as a powerful analogy for divine sovereignty and freedom. Just as the multiverse contains many alternate outcomes, God’s will is not bound by any single chain of events – any chain is within His power. The multiverse idea can thus artistically illustrate the concept of contingency under divine will: imagine God surveying the branching multiverse of all possibilities and “choosing” (or upholding) a particular thread as the experienced reality. Al-Ghazali would say that in fact God does choose one thread (the one we live in) at each moment. The existence of the other branches in MWI can be likened to the idea that those other outcomes were genuinely possible and known to God. In Islamic thought, God’s knowledge is said to encompass all possibilities, even those never actualized. MWI gives a vivid picture of possibilities as actualized (albeit in separate worlds), which can deepen appreciation of the idea that nothing limits God except His own will. If even physics permits a kind of “all possible events happen” scenario, it offers a striking parallel to the theological notion that reality could have been entirely different had God willed it – and in the multiverse it actually is different elsewhere.

Tensions: Determinism vs. Divine Volition

Despite these intriguing parallels, there are significant tensions and contrasts between MWI and al-Ghazali’s occasionalism. Any attempt to relate them must confront these differences:

• Deterministic Law vs. Volitional Agency: MWI’s multiverse unfolds mechanistically. Once the initial state and laws are set, the entire branching structure of reality follows inevitably (there is no outside intervention or choice at each branch). Al-Ghazali’s doctrine, in contrast, insists on active, moment-to-moment divine choice. God is a personal agent who decides what happens at each occasion, not a passive law. The MWI multiverse could be seen as akin to a deistic scenario – if one imagined God in it at all, He would have set up the wavefunction and its laws at the start, and then “let it run” deterministically, producing all outcomes. But that picture strips away the volitional, responsive God that occasionalism emphasizes. Al-Ghazali’s God can answer prayers, perform miracles (deviations from the usual pattern), and inject purpose into each event. The Everettian multiverse, by itself, has no concept of preference or purpose – everything that can happen, does happen, regardless of value or divine intent. This deterministic character of MWI conflicts with the idea that God selects one outcome in accordance with a divine purpose.
• Singular History vs. Multiple Actualities: Occasionalism is still a doctrine about one world’s history – the one we experience, continually governed by God. Al-Ghazali did not suggest that God creates multiple simultaneous universes. In fact, his emphasis is on the absolute unity of God’s control over this world’s events. MWI posits many equally real histories. If one tried to incorporate God into MWI, one faces the question: does God will all these worlds into being? If so, what is the relationship between divine justice or providence and the fact that every conceivable outcome (even those where, say, evil prevails) exists somewhere? For a religious worldview, having all possibilities actual can be troublesome – for instance, one branch might have a person living a righteous life and another branch where that same person makes horribly immoral choices. Does God endorse both? Occasionalism, as traditionally understood, would say God’s will actualizes a particular course for a good reason (even if that reason is inscrutable). The multiplicity of MWI might seem to undermine the idea of a coherent divine plan for creation, replacing it with an indifferent explosion of possibilities. This is a serious tension if one were to literally merge the concepts. Theologically, one might have to interpret the multiverse in a limited way (e.g. God allows all physically possible outcomes, but moral or metaphysical realities might still differ – a complex and speculative adjustment).
• Contingency in Occasionalism vs. Inevitable Multiverse: Al-Ghazali’s contingency means the world could have been otherwise, but only one outcome happens – by God’s will. The multiverse says the world is otherwise in other branches simultaneously. In occasionalism, unrealized possibilities remain abstract; in MWI, they become concrete. This raises the question of divine choice: if God in some sense brings about the multiverse, is He choosing anything at all, or just letting every option play out? That could conflict with the concept of God’s will being exercised in a meaningful way. It almost suggests a scenario where God’s will is “to create all possibilities” rather than to choose a specific world. This would be a very different theological stance, arguably at odds with Islamic teachings that stress purposeful divine action and moral order (God chooses the world where His purposes are fulfilled, not all imaginable worlds indiscriminately).
• Moral and Theological Implications: Occasionalism is tied to a theological context – for instance, it upholds miracles and highlights reliance on God (since only God causes anything). MWI, by contrast, is morally inert; it doesn’t distinguish a miracle branch from a normal branch except by amplitude (and in standard physics all branches obey the same natural laws, miracles in the sense of violations of physics would not occur unless those events had nonzero amplitude and even then they’d just be part of the multiverse with extremely low measure). If one tries to overlay occasionalism onto MWI, one might imagine that what we call miracles are simply extremely low-probability branches that normally we don’t witness – but if all branches exist, those “miraculous” branches exist too. Does that cheapen miracles (since they happen somewhere anyway)? Or would one say God’s special acts correspond to certain branches being given higher “weight” or something? These are speculative thoughts, but they illustrate the tension: MWI’s impartial proliferation of outcomes doesn’t align with a God who chooses certain outcomes for divine reasons. The role of chance is also tricky – in our single world, occasionalism might interpret quantum randomness itself as God’s choice in each case (thus not random at all). But MWI says there is no fundamental randomness, just branching. If God were controlling each quantum event under occasionalism, He collapses the wavefunction by fiat. MWI says no collapse happens. These are philosophically different paradigms – one personal and willful, one impersonal and automatic.

Given these tensions, a literal reconciliation of MWI with al-Ghazali’s occasionalism would be problematic. The spirit of occasionalism is deeply theistic and intentional, whereas MWI as usually understood is an elegant but coldly mechanistic ontology. However, the exercise of comparing them is illuminating. It forces us to ask: what aspects of reality do we take as given (one world vs many? fixed causal laws vs constant divine sustenance?), and how might things look if we switch those assumptions?

Conclusion: Reframing Occasionalism in a Quantum Multiverse

While MWI and al-Ghazali’s occasionalism emerge from entirely different worldviews, exploring their conceptual intersection yields fresh perspectives on both. MWI’s extravagant ontology – countless parallel worlds – serves as a metaphor for contingency and divine freedom. It illustrates in a vivid physical way that what happens need not be the only thing that could have happened. This resonates with al-Ghazali’s insistence that the natural order has no autonomous necessity; it is wholly dependent on God’s will, which could at any moment produce a different outcome. The radical plurality of MWI can be seen as an analogical mirror to the radical contingency of occasionalism.

Using MWI constructively, one might say it provides a sort of “thought experiment” for theology. It encourages imagining a God so powerful that no possibility is left uncreated – a multiverse as a display of infinite creative act. It can also help reframe occasionalism in more modern terms: just as the quantum wavefunction underlies and generates the classical appearances, one could analogize that God’s continual creative command underlies and generates the phenomena we call causation. The many worlds branching might even be used to explain how God’s single decree could contain within it all particular outcomes for different observers (somewhat like different worlds for different choices). These are speculative analogies, but they show that Islamic occasionalism can find surprising intellectual companionship with modern physics interpretations. Each challenges a straightforward material causality and invites deeper questions about how reality operates behind what we observe.

Ultimately, MWI should probably be invoked metaphorically rather than literally in theological discourse. It may not be that God actually created the quantum multiverse in the Everettian sense – Occam’s razor (and Philip Ball’s critique) might warn us not to multiply worlds without necessitytheo-puzzles.ac.uktheo-puzzles.ac.uk. However, as a metaphor, the idea of branching worlds can reinvigorate occasionalism’s core principle: that the world as we see it is just one of many ways it could be, and it exists at each moment only by the specific choice of the Divine. In an age where science often points to indeterminacy or multiplicity, drawing a bridge from MWI to al-Ghazali’s thought can provide a philosophically rigorous and accessible way to discuss divine volition, determinism, and contingency. It shows that the ancient insight – that “no cause other than God can necessitate its effect… it is always possible that God might will a different effect”bu.edu – can find an unexpected echo in the strangest halls of modern physics. Even if one does not accept MWI as physically true, its vision of “many worlds” can spur constructive reflection on God’s relationship to a world of quantum uncertainty.

In conclusion, exploring MWI alongside al-Ghazali’s occasionalism invites us to imagine a reality where every flicker of possibility is acknowledged – either by existing in a parallel universe or by lying within the boundless power of the Divine. This imaginative bridge does not resolve all conflicts between science and theology, but it enriches the conversation. It highlights profound themes common to both: the idea that what is rests on a vast backdrop of what could be, and that at the foundation of reality – whether one speaks in terms of a universal wavefunction or the will of God – lies something unitary, beyond the ordinary causal story, giving rise to the world we experience. Such dialogue between MWI and occasionalism ultimately reframes Islamic occasionalism not as a quaint medieval notion but as a provocative viewpoint that can engage with cutting-edge ideas about quantum reality, encouraging believers and skeptics alike to ponder the mystery of how and why events happen as they do in our world (when so much else was possible).

Sources:

1. Everett, Hugh (1957). “Relative State” Formulation of Quantum Mechanics. (Original proposal of MWI)
2. Stanford Encyclopedia of Philosophy – Many-Worlds Interpretation of Quantum Mechanics plato.stanford.edu en.wikipedia.org
3. Stanford Encyclopedia of Philosophy – Occasionalism (Malebranche’s formulation) plato.stanford.edu
4. Stanford Encyclopedia of Philosophy – al-Ghazali (determinism and God’s causal plan) plato.stanford.edu
5. Wikipedia – Many-Worlds Interpretation (overview of branching and decoherence) en.wikipedia.org
6. Vedral, Vlatko – “Occasionalism and Quantum Entanglement” (Al-Ghazali on causation) vlatkovedral.com
7. Adamson, Peter – “Al-Ghazali, Causality, and Knowledge” (analysis of Ghazali’s 17th discussion) bu.edu
8. Quanta Magazine – Philip Ball, “Why the Many-Worlds Interpretation Has Many Problems” (description of MWI’s multiverse) quantamagazine.org
9. The Quran and Science blog – “Quantum Mechanics and al-Ghazali’s Occasionalism” (simplified summary of occasionalism) thequran.love
10. Theological Puzzles blog – Qureshi & Hurst, “Problem of Evil and Many Worlds” (Everett and theological implications)theo-puzzles.ac.uk (for historical context on Everett).