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Evaluating the philosophical probability that our reality is a computer-generated simulation.
If you were living in a hyper-realistic video game, how would you know? If the graphics were perfect and the physics were flawless, would the 'real world' even matter anymore?
Long before computers, the Greek philosopher Plato proposed the Allegory of the Cave. He imagined prisoners chained in a cave, seeing only shadows of objects cast on a wall by a fire. To the prisoners, these shadows are 'reality.' If one prisoner escaped and saw the sun, they would realize their previous life was a mere projection. In modern terms, the Simulation Argument suggests our entire universe might be those shadows—a digital projection created by a 'post-human' civilization. This creates an epistemological crisis: if our senses can be deceived by a perfect imitation, how can we claim to know anything about the 'true' world?
Quick Check
In Plato's Allegory, what do the shadows on the wall represent in the context of modern simulation theory?
Answer
The shadows represent the perceived physical world (our 'reality') which may actually be a secondary projection or simulation of a higher truth.
In 2003, philosopher Nick Bostrom formalized this idea into a logical trilemma. He argued that at least one of the following three statements must be true: 1. Civilizations usually go extinct before reaching a 'post-human' stage (capable of running high-fidelity simulations). 2. Post-human civilizations have almost no interest in running 'ancestor simulations.' 3. We are almost certainly living in a simulation. Bostrom’s logic relies on Substrate Independence—the idea that consciousness doesn't require a biological brain, but can emerge from silicon chips if the computation is complex enough.
Imagine there is 1 'Base Reality' civilization. They decide to run 1,000 ancestor simulations.
Quick Check
According to Bostrom, if a civilization reaches a post-human stage and chooses to run many simulations, what happens to the probability that we are in the 'Base Reality'?
Answer
The probability decreases significantly as the number of simulated realities far outnumbers the single base reality.
The greatest challenge in simulation theory is Epistemological Circularity. If a simulation is 'perfect,' it simulates the laws of physics exactly. Any experiment we perform inside the simulation (like smashing atoms in a collider) would yield the results programmed by the simulators. This is similar to René Descartes' 'Evil Demon' hypothesis—the idea that an all-powerful being could be tricking your senses into perceiving a world that isn't there. If the simulation is seamless, there is no 'glitch' to find, making the theory unfalsifiable.
Consider the 'Nested Simulation' problem. If we are in a simulation, we might eventually build our own supercomputers to run simulations of our own.
1. Level 0: Base Reality. 2. Level 1: Our Reality (Simulated). 3. Level 2: Our Simulations (Simulated by us).
Critics argue that simulating a whole universe is impossible due to the Bekenstein Bound, which limits the amount of information that can be stored within a finite physical space.
1. To simulate every subatomic particle in the universe, the 'host' computer would need more atoms than exist in our universe. 2. However, simulators could use Lazy Evaluation (a programming trick): only render the parts of the universe that are currently being observed by a conscious mind. 3. This leads to the 'Quantum Observer' hypothesis: perhaps particles only have definite positions when measured because the simulation is saving processing power.
Which of the following is NOT one of the three possibilities in Bostrom's Trilemma?
What does 'Substrate Independence' imply?
The 'Lazy Evaluation' argument suggests that a simulation might only render objects when they are being observed to save computing power.
Review Tomorrow
In 24 hours, try to explain the three parts of Bostrom's Trilemma to a friend without looking at your notes.
Practice Activity
Research the 'Double Slit Experiment' in quantum physics and write a short paragraph on why some people believe it provides evidence for 'Lazy Evaluation' in a simulated universe.