The advantage of being Elon Musk is that when he says something, people shut up and listen.

After all, Musk is the technology entrepreneur who made a couple of billion dollars creating companies like PayPal, and he’s now putting his money where his vision is – on projects like the Tesla electric car and the Space X programme. So, when Musk told a Silicon Valley conference recently that he believed the odds were that human beings lived inside a cosmic computer simulation (like in the film, The Matrix), it triggered a great deal of buzz on the internet.

What Musk said was not exactly new. Scientists, sci-fi writers and philosophers have said it in some way or the other going back, arguably, all the way to the Bhagavad Gita, and its concept of maya or illusion. But the difference is that Musk presented his claim with a startlingly simple logic.

Musk pointed out that just 40 years ago, computer games meant Pong, which was played using just two rectangles and a dot. But now, said Musk, computer games are photorealistic 3D simulations with millions of people playing games simultaneously – and it’s getting more sophisticated every year.

Before long, said Musk, computer games will become completely immersive and “indistinguishable from reality” itself. Thus, Musk asked: if we fast-forward 10,000 years into the future, imagine what games and simulations will be like then?

The universe probably has many advanced civilisations whose members have the ability of creating such advanced simulations, said Musk. Hence, there are probably billions of simulated worlds while there is, of course, only one real world. Therefore, Musk concluded, “the odds that we’re in base reality [the real world] is one in billions”. Maybe we’re just lines of code in a simulation created by our own distant descendants 10,000 years in the future.

Hey, hang on a minute

When the billionaire inventor made that assertion, people’s first reaction was to nod and connect his theory with what had come before – whether the concept of maya as presented in the Gita, or the adventures of Neo in The Matrix, or the work of philosopher Nick Bostrom or physicist Silas Beane who have done research in related areas.

But now it’s time to say, hey, hang on a minute, that ain’t necessarily so.

Psychology professor Ricardo Manzotti and cognitive scientist Andrew Smart have come up with a spirited refutation of Musk’s theory. Their argument is not always easy to follow, but the essential point they make is this: Simulations are made of the same stuff that everything else is made of – hence they are the same as reality. For example, a 10-inch model of Mount Everest is still made of the same stuff that everything else is made of, hence it is the same as reality. Nowhere, in fact, do we find a pure simulation that is not an object. The idea that we might mistake a simulation of the world for the world itself is thus flawed, both conceptually and empirically.

Occam’s Razor

There is, however, a much more basic argument against Musk’s claim, based on Occam’s Razor, a philosophical concept, which essentially says that if you have two theories that explain the observable facts, you should use the simpler of the two – at least until more evidence comes along. The razor therefore helps cut through a problem, and slice away its unnecessary elements. As one of its iterations puts it: “When you hear hoof-beats behind you, think horses, not zebras."

Thus, to look at our world and say that it is not reality but a computer simulation created by a race of super beings is not too different from looking at the pyramids and saying they were built, not by the ancient Egyptians, but by visiting aliens who came to earth long ago in a giant purple flying saucer.

Or, to look at the issue another way, we would do well to follow cosmologist Carl Sagan’s dictum that “extraordinary claims require extraordinary evidence". In other words, if someone makes a strange claim, they must be able to present evidence that is proportionate to its strangeness. Thus, the stranger the claim, the stronger the evidence needed to justify it.

The fact is that today we have various theories, including Musk’s, about how our world is a cosmic computer game, and we are just virtual playthings in it, but we have no evidence of this. And that is ok to the extent that we always need theories like these for human knowledge to progress. However, it is only once someone presents us with some actual evidence, in proportion to the strangeness of this claim, that we truly take the matter seriously.

If it looks like a duck…

There are other arguments against Musk’s simulation theory too, which range from the pragmatic to the outright adventurous.

For instance, take the argument that says if our world was indeed a simulation, its creators would be very careful to hide that fact from us, its inhabitants. Because if we ever realised that we existed in a simulation, and not in the real world, it could be a threat to their very purpose (which is why, in The Matrix, the agents were so desperate to hunt down and eliminate Morpheus and his rebels before they could spread their secret knowledge). Hence the very fact that Elon Musk is still around – and has not been quietly eliminated from our midst, along with all traces of his theory – would suggest that this is not a simulation, but a real world.

However, let us resist the temptation to get overly adventurous with our arguments. Let’s keep them simple and apply the very sensible duck test, which says, “If it looks like a duck, and walks like a duck, and quacks like a duck, let us say it IS a duck”.

So if our world looks real, feels real, and sounds real, let us say, for now, that it IS real. Until such time, of course, that some further evidence comes in.

Sorry about that, Elon Musk.