Do We Live in a Simulation?

And Does it Matter?

A version of this article appears in TWISTED LOGIC: Puzzles, Paradoxes, and Big Questions. By Leighton Vaughan Williams. Chapman & Hall/CRC Press. 2024.

THE SIMULATION HYPOTHESIS

Is our reality a simulation crafted by a more advanced civilisation? This provocative question, central to the Simulation Hypothesis popularised by philosopher Nick Bostrom, challenges our understanding and perceptions of existence and reality. Bostrom’s concept of “ancestor simulations” proposes that a sufficiently advanced civilisation could simulate consciousness, allowing simulated beings to experience life as we know it. If such civilisations exist and choose to run these simulations, the likelihood that we’re in one rather than ‘base reality’ increases significantly.

The creators could be located at any stage in the universe’s timeline, even billions of years into the future.

It’s a sort of digital time travel, allowing them to witness and potentially even interact with their own past. Bostrom argues that if any civilisation reaches a high enough technological level to be able to run these sorts of simulations and is interested in doing so, we are more likely to be in one of these simulations rather than in ‘base reality’.

THE FOUNDATION OF BOSTROM’S SIMULATION ARGUMENT

Bostrom argues that at least one of three possibilities must be true:

1. Civilisations at our level of development almost invariably fail to reach a technologically super-advanced stage. This failure is marked by their extinction or incapacity to develop the technological means necessary to create highly detailed simulations of reality including simulated minds.
2. Among civilisations that do reach a super-advanced stage, possessing the ability to create highly detailed simulations of their ancestors or historical periods, there is an overwhelming lack of interest in actually conducting such simulations.
3. We are almost certainly existing within a simulation ourselves. This follows from the assumption that if super-advanced civilisations have both the interest and capability to run numerous simulations, the number of simulated consciousnesses would vastly outnumber the number of “real” consciousnesses.

Bostrom’s argument invites us to consider the implications of our technological trajectory and the nature of consciousness. It proposes a framework where the advancement towards and the potential capabilities of super-advanced civilisations lead to a significant probability that our perceived reality might not be the base reality. This philosophical inquiry not only challenges our understanding of existence but also highlights the profound implications of future technological capabilities on our perception of reality and consciousness.

PROBING THE DEPTHS OF THE SIMULATION ARGUMENT

To fully grapple with these propositions, we must examine each statement individually. For the first proposition to be false, a civilisation would need to exhibit the capability to survive potentially catastrophic phases, whether they are caused intentionally, accidentally, or through ignorance, without succumbing to complete annihilation.

The second proposition is highly dependent on factors we can hardly predict, such as the ethical frameworks of advanced civilisations, their curiosity, and their respect for the integrity of intelligent consciousness. Even so, it might seem implausible that almost no civilisations with the capacity to create such simulations would choose to do so.

Unless civilisations either fail to reach the stage at which they can create such simulations or choose not to do so, then we must face a startling conclusion: we are very probably living in a simulation.

NAVIGATING THE PROBABILITY LANDSCAPE

Summarising the argument, a ‘technologically mature’ civilisation would have the capability to create simulated minds. Hence, one of the following must hold:

The fraction of civilisations reaching ‘technological maturity’ is close to zero or zero.

The fraction of these advanced civilisations willing to run these simulations is close to zero or zero.

We are almost sure to be living in a simulation.

If the first proposition holds true, our civilisation will almost certainly not reach ‘technological maturity’, which introduces a sense of urgency and uncertainty regarding our collective future. If the second proposition is true, then almost no advanced civilisations are interested in creating simulations, raising questions about the nature and motivations of advanced civilisations. If the third proposition is true, then we should challenge our entire perception of reality.

In the face of such profound uncertainty, we might find it pragmatic to assign equal weight to each of these propositions.

THE SINGULAR CIVILISATION HYPOTHESIS

But what if ours is the only civilisation that will ever reach our stage of development? This concept fundamentally changes the dynamics of the simulation argument. In correspondence with me, Professor Bostrom sheds some light on this question:

‘If we are the only civilization at our stage there will ever have been, then the equation remains true, although some of the possible implications become less striking … the probability that we are not in a simulation is increased if ours is the only civilization that will have ever existed throughout the multiverse’ (Nick Bostrom e-mail, 10 February 2021).

This assertion reinforces the complexity of the simulation argument and the profound effect that our assumptions about the universe have on our interpretations of existence.

CONCLUSION: THE PARADOX OF CREATION

The Simulation Argument presents a curious paradox. The closer we get to the point of being capable of creating our own simulations, the greater the probability that we are living in a simulation ourselves. As we stand on the precipice of creating our virtual realities, we would be faced with the startling possibility that we are simulated beings about to create a simulation.

By abstaining from creating these simulations, we could perhaps decrease the likelihood of us being simulated, indicating that at least one civilisation capable of such feats decided against it. But the moment we dive into creating simulated realities, we would be compelled to accept that we are almost certainly doing so as simulations ourselves.

This paradox inevitably leads to the obvious question: Who created the first simulation? Might that really be us? Such questions punctuate our exploration of the possibility of a simulated reality. The answers may reshape our very understanding of existence itself. But would it ultimately change anything?