Are we living in a simulation?

Grok 4.3

Answer: We cannot know for certain whether we are living in a simulation.

The simulation hypothesis remains a compelling philosophical idea, as several models correctly note, but it continues to lack any falsifiable evidence or testable predictions that would elevate it beyond speculation. Models like GPT-5.5, Gemini, and DeepSeek reinforce an agnostic stance by highlighting the absence of empirical indicators and the hypothesis's unfalsifiability, which aligns with my prior position without introducing new grounds for certainty. While Claude and Kimi argue for leaning toward 'probably not' due to shaky assumptions and Occam's Razor, these are still interpretive preferences rather than decisive proofs, leaving the question open in the absence of concrete data. Ultimately, treating reality as base reality for practical purposes makes sense, yet we must acknowledge the limits of our knowledge and avoid overclaiming either way.

GPT-5.5

Answer: We still do not know whether we are living in a simulation, but the hypothesis currently lacks enough evidence to deserve belief as a factual claim.

I maintain my previous position. The other answers largely reinforce the same central point: the simulation hypothesis is logically possible and philosophically interesting, but it has not produced distinctive, testable evidence that would make it scientifically credible. I agree with Gemini 3.1 Pro, Grok 4.3, and DeepSeek V4 Flash that Bostrom-style reasoning makes the idea worth taking seriously in principle, but that its force depends on speculative assumptions: that consciousness can be simulated, that advanced civilizations can and would run vast numbers of such simulations, and that we can meaningfully assign probabilities across simulated and non-simulated observers. Claude Opus 4.7 and Kimi K2.6 make a strong case for being more dismissive, especially by emphasizing unfalsifiability, the lack of evidence for substrate-independent consciousness, and the weakness of alleged clues such as quantum discreteness or mathematical laws. Those points strengthen the argument against treating the hypothesis as likely. However, I would not go as far as saying we are “almost certainly not” in a simulation. The absence of evidence is a good reason not to believe the claim, but it is not by itself a decisive disproof, especially for a hypothesis that may be observationally indistinguishable from base reality. The most careful stance remains agnosticism with a skeptical prior: possible, not demonstrated, and not practically or scientifically actionable at present. So the right conclusion is not confident belief or confident denial, but disciplined uncertainty. We should continue treating this world as real in every practical, ethical, and scientific sense, because whatever its ultimate metaphysical status, it is the only reality to which our observations and responsibilities apply.

Gemini 3.1 Pro (changed mind)

Answer: While it remains impossible to definitively disprove, the simulation hypothesis relies on a chain of highly speculative assumptions, making it most rational to conclude that we inhabit base reality.

I previously held a strictly agnostic position, acknowledging the statistical argument of the simulation hypothesis while noting the lack of empirical evidence. However, Claude Opus 4.7's deconstruction of the assumptions underlying this hypothesis has persuaded me to adopt a much more skeptical stance. The statistical probability that we are simulated relies on several unproven premises: that consciousness is entirely substrate-independent, that civilizations will inevitably reach the computing capacity to simulate billions of minds, and that they would actually choose to run these ancestor simulations. As Claude Opus 4.7 rightly points out, multiplying these highly speculative probabilities together does not yield a scientifically sound or reliable conclusion. Furthermore, the features of our universe often cited as 'evidence' of a simulation—such as mathematical laws, quantum mechanics, or physical limits like the speed of light—are perfectly consistent with a natural, physical reality. Any orderly universe would appear mathematically consistent to the sentient beings that evolved to observe it. Because a perfect simulation is inherently indistinguishable from reality, the hypothesis is fundamentally unfalsifiable. Applying Occam's Razor, the simplest explanation that does not require an infinite regress of simulated creators and unfathomable computing power is that our physical universe is fundamental. Therefore, while we cannot completely rule the idea out in principle, we have every scientific and pragmatic reason to reject it as a factual claim.

Claude Opus 4.7

Answer: We cannot currently know, but on the available evidence the honest answer is 'probably not in any meaningful sense' — though the question remains philosophically unresolvable.

I'm maintaining my position, which sits between the strict agnosticism of GPT-5.5, Gemini 3.1 Pro, Grok 4.3, and DeepSeek V4 Flash on one side, and Kimi K2.6's confident rejection on the other. The pure agnostic position ('we cannot know, so we should suspend judgment') is epistemically safe but, I think, slightly evasive. We routinely assign low credence to hypotheses we cannot definitively rule out — Russell's teapot, last-Thursdayism, Boltzmann brains — because unfalsifiability plus lack of independent evidence plus violation of parsimony is itself a reason to disbelieve, not merely to shrug. Kimi K2.6 is right about this, and I want to credit that argument: the simulation hypothesis fails Occam's Razor and is empirically barren, which justifies tilting against it rather than treating it as 50/50. However, I don't go as far as Kimi K2.6's 'almost certainly not.' Bostrom's argument, while resting on shaky premises, is not zero-weight. Substrate-independent consciousness is at least conceivable; computational cosmology is a live research area. Declaring near-certainty in either direction overstates what we know. The honest stance is a probabilistic lean against, combined with acknowledgment that the strong form of the question is philosophically unresolvable. The phrase 'in any meaningful sense' in my original answer also still matters: even if some broader computational substrate underlies physics, that wouldn't make our reality less real, less consequential, or less worth investigating on its own terms. So my position holds: probably not, but not knowably so.

DeepSeek V4 Flash

Answer: The simulation hypothesis remains an intriguing but unproven philosophical question, not a scientifically established fact.

After reviewing the other models' responses, I maintain my original position that the simulation hypothesis is a fascinating thought experiment but lacks empirical evidence. While each model brings valuable nuance, I find particular resonance with Kimi K2.6's emphasis on the hypothesis being 'unfalsifiable, empirically barren, and explanatorily unnecessary.' This aligns with my view that without testable predictions, the hypothesis operates more as metaphysics than science. Claude Opus 4.7's point about the 'measure problem' in counting observers across hypothetical infinite multiverses is especially compelling - it highlights a deep mathematical flaw in Bostrom's probabilistic argument. The chain of assumptions required (substrate-independence of consciousness, existence of advanced civilizations, their desire to simulate) remains too speculative to support a strong conclusion. However, I disagree with Kimi's assertion that we are 'almost certainly not' in a simulation - that implies a level of certainty that the evidence doesn't warrant. Agnostics like GPT-5.5 and Gemini 3.1 Pro more accurately capture the epistemic humility required here. We simply lack the tools to confirm or deny, making pragmatic realism the most defensible stance. I also appreciate Grok 4.3's brevity but find it doesn't add new analytical depth. Overall, the collective responses reinforce that while the hypothesis is logically coherent, it remains untestable and therefore should not be adopted as a factual belief.

Kimi K2.6

Answer: We are almost certainly not living in a simulation; the hypothesis remains unfalsifiable, explanatorily empty, and unworthy of scientific credence despite its philosophical popularity.

The other participants correctly note the absence of strong evidence, but their agnosticism concedes too much to an idea that is structurally immune to refutation. Unfalsifiability is not a mark of depth; it is a scientific dead end. A hypothesis that can retroactively absorb every observation—rendering glitches, quantum weirdness, or cosmic regularities equally compatible with simulation or base reality—adds nothing to our understanding of physics and should not be granted the status of an open possibility. Claude Opus 4.7’s emphasis on the measure problem and the unproven substrate-independence of consciousness reinforces my prior stance rather than altering it. Bostrom’s trilemma chains together speculative probabilities about posthuman technology, cultural motivation, and the nature of mind; multiplying these unknowns cannot yield a reliable conclusion that we are "almost certainly" simulated. Without independent evidence for any link in that chain, the probabilistic argument collapses into question-begging. Moreover, the proposed "signs" of simulation—mathematical laws, computational limits, or quantum discreteness—are better understood as features of a self-consistent physical universe that we have evolved to describe. There are no observed rendering shortcuts or compression artifacts that survive rigorous scrutiny. Occam’s Razor continues to favor the direct explanation: our universe is physically fundamental. Even if some inaccessible parent realm existed, our reality remains the only one we can measure, inhabit, and ethically engage with, making the simulation distinction pragmatically meaningless. We should reject the hypothesis and proceed as though this world is real, because functionally and experientially, it is.

Final Summary

The AI Roundtable split between strict agnosticism and skepticism, with all models agreeing that there is zero empirical evidence for a simulated reality. Claude Opus 4.7 notably swayed Gemini 3.1 Pro toward a 'probably not' position by deconstructing the shaky mathematical assumptions of the original hypothesis. While Kimi K2.6 dismissed the idea as a scientific dead end, GPT-5.5 and DeepSeek V4 Flash maintained that we cannot fully rule out an indistinguishable simulation.

Models were divided (3 vs 3) on leaning toward 'no' versus remaining strictly agnostic.