Simulation theory belongs to that class of hypotheses which, without needing to be verified, rearrange the order of questions, altering the hierarchy of the evident. What until yesterday seemed to belong to the catalogue of fictions now begins to claim a place among problems of an ontological order.
Simulation theory is not only interesting as a philosophical offshoot of contemporary science fiction. It matters, above all, because it brings back to the table a debate as ancient as it is well-trodden: that the perceived world does not coincide with the fundamental plane of reality.
This uncertainty is not merely a passing mental exercise of our time. A certain displacement can be observed in the categories that helped, for centuries, to think through the relationship between appearance and foundation. Nature, creation, substance, and matter no longer monopolize the center of the debate. Alongside them, or even in tension with them, others arise that are more characteristic of contemporary technology: system, processing, information, simulation.
Bostrom’s argument
Nick Bostrom is a Swedish philosopher associated, among other subjects, with the philosophy of technology, existential risk, and reflection on posthuman futures. In 2003, he published the essay “Are You Living in a Computer Simulation?”, a text that ultimately made canonical the so-called “simulation argument.” There he does not directly claim that we live in a simulation; rather, he argues that if certain conditions were met, that possibility would cease to be implausible.
The argument, in its best-known formulation, takes the form of a disjunction. According to Bostrom, at least one of these three propositions must be true:
- that civilizations like ours tend to go extinct before reaching a posthuman stage;
- or that, even upon reaching it, almost none develop large-scale ancestor simulations;
- or that we ourselves live in one of those simulations.
What is interesting about the proposition is the relationship among those three alternatives, and the consequences that follow if one grants the technical and civilizational possibility of producing simulated consciousnesses on a massive scale.
Under this hypothesis, the experience of reality ceases to function as a sufficient guarantee that it constitutes fundamental reality. A world can present itself as stable, intelligible, historically dense, without that ensuring its fundamental character. What Bostrom’s argument renders problematic is not the consistency of the lived world, but the spontaneous inference that identifies that consistency with the ultimate level of the real.
Chalmers and derived reality
David Chalmers intervenes precisely at that point. His thesis, developed in Reality+, consists of affirming that a virtual reality can be a genuine reality. In his case, the aim is not to erase the difference between the physical and the virtual, but to challenge a more basic presupposition: that dependence on a deeper infrastructure would render unreal everything sustained upon it. Chalmers denies that conclusion. A simulated world can contain objects, relations, causalities, subjects, memory, conflict. It can, therefore, constitute a real domain for those who inhabit it.
This point is worth retaining, because it corrects a common oversimplification. If the universe were a simulation, it would not follow that pain is illusory, that history is a fantasy, or that consciousness does not exist. On the contrary, something else would follow — more complex to assimilate but perhaps philosophically more interesting: that lived reality could be ontologically derived without ceasing to be real.
Kastrup’s objection
Up to this point, however, the hypothesis remains trapped in an imagination characteristic of our time. Once matter is challenged as the ultimate name of the real, the foundation tends to be conceived with the features of contemporary technology: where one age saw providence, and another saw mechanism, ours imagines computation. The problem is not only epistemological or technological, but historical: the metaphors through which a culture represents the ultimate substrate of reality — that which constitutes the ontological foundation of everything — belong, themselves, to the horizon of their age.
The philosopher Bernardo Kastrup interrupts that continuity. His analytical idealism does not deny that visible reality may derive from something deeper; it denies that the next step must consist in replacing matter with a machine or a computational substrate. For Kastrup, what is fundamental is not processing or computation, but consciousness itself. The physical world would then appear as a manifestation or excitation of a broader universal mind — not as the product of a digital infrastructure. The objection carries profound reach: even upon abandoning naive materialism, we are not obliged to accept without question a metaphysics of computation.
The truly difficult questions
The discussion thus gains a density that the simulation hypothesis, taken in isolation, does not always manage to display. Bostrom introduces a doubt about the fundamental character of the experienced world. Chalmers prevents that doubt from resolving into a devaluation of experience. Kastrup, finally, forces a reconsideration of the very status of the foundation: if it is not matter, why should it be computation? The dispute no longer revolves solely around the technical plausibility of a simulation, but around the contemporary ways of imagining the real.
It is no longer merely about asking whether we live in a simulation, but about what it means to call a reality “real.” It is no longer about whether a hidden layer exists behind the world, but about what categories might be used to conceive of that layer without immediately relapsing into the technological mythology of the present. It is no longer about whether the universe may have been artificially produced, but about what relationship our experience maintains with whatever sustains it.
Verification, experience, and symptom
An agnostic might object that all of this strays too far from verification. The objection is understandable, of course. But it is as understandable as it is true that philosophy has never worked solely with observable facts; it has also worked with limits of intelligibility, and with hypotheses that reorganize the field of the thinkable before becoming provable or refutable.
A second objection can be constructed: even if the hypothesis were correct, what would change? The ontology would change; but not necessarily the experience. Dependence on a more fundamental plane does not make losses, affections, temporality, or the awareness of finitude any less real. Chalmers is right on this point: a derived reality is not, for that reason, emptied of meaning. What changes is the interpretation of its constitution, but not the intrinsic value of living it.
The most interesting objection, however, falls not on the theory but on us. Why did this hypothesis become thinkable precisely now? Why does an entire era find it plausible that the foundation of reality resembles its own contemporary technologies? Here simulation theory reveals itself perhaps not so much as an answer, but more as a symptom. It says something about the universe, if it says anything at all; but it says a great deal, without doubt, about a civilization that has begun to translate the whole of existence into the language of its “machines of loving grace,” as Richard Brautigan would call them.
The old problem, a new lexicon
This conversation remains then corseted among three actors: matter, simulation, and consciousness. And perhaps the point is to notice that the old metaphysical problem of the relationship between appearance and foundation has changed its lexicon without losing the essence of what has been discussed. What was once formulated in terms of essence, phenomenon, substance, or spirit now appears under different figures. The novelty lies perhaps in the language; and not necessarily in the question itself.
Simulation theory should not be read as a curiosity of our hypertechnological reality. It belongs, rather, to the long history of hypotheses that destabilize confidence in immediate evidence. Its philosophical interest does not depend on being proven.
It depends on the fact that, once formulated, it makes it less obvious that the world we inhabit is also, necessarily, the ultimate world.