How does VR provide justification to the "Brain in the Vat" hypothesis?

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Scepticism about the external world is an idea which is begrudgingly acknowledged within philosophy; it seems to absurd to suggest that there is no external world, yet it cannot be refuted. This gives rise to the “Brain in the Vat” hypothesis, which suggests that there may be no external world. Instead, the sensations presented to us are provided by a computer which is hooked up to our brain floating in a vat. Most people would view this as nonsensical and dismiss it immediately. However, this article will argue that a thought experiment could provide some evidence towards the “Brain in the Vat” hypothesis and as such would suggest that it is a stronger theory than it is given credit for. Despite this, the article will not argue for the “Brain in the Vat” hypothesis. Instead, it will strengthen its position.

Scepticism about the external world arises due to the Vale of Perception provided by theories related to indirect realism. This is because such theories suggest that what we are directly perceiving is mind dependant; the qualities which we believe objects to have exist only in our mind. Consequently, we can never be sure of the true nature of the external world as we can not step beyond the vale. We cannot occupy a “God’s Eye View” of what the world actually looks like and therefore the exact nature of the external world is unknown.

Some philosophers take this a step further and suggest that we cannot be sure that there is in fact an external world. This causes the arise of multiple different ideas, such as idealism ( the idea all qualities are mind dependant) and solipsism (the only thing that exists is my mind alone).

A suggestion which particular arises from these two positions is the “Brain in the Vat” hypothesis. Imagine that in the future, you are forced to remove someone’s brain due to the injury of the rest of their body. In order to keep it alive, you put it in a vat ( a container with liquid that keeps the brain alive). Over time, you are slowly able to connect this brain to a computer which provides the brain with stimulation which make it appear to the brain they are in a different world. It is suggested that this brain could in fact be you right now. There may be no external world at all. Instead, you are a brain hooked up to a computer which makes it appear to you that there is an external world.

This is a slightly uncomfortable position. There is no way of categorically proving that we are not brains in vats due to the Vale of Perception. However, it is a mostly discarded idea. One of this is due to the idea of infinite regress. How do we know that the scientist who put us into the vat isn’t in a vat himself. If so, who put them into the vat? Is this person also in a vat. The idea of being in a vat leads to infinite regress, were we never stop looking for the answer. Most often, philosophers reject the idea of infinite regress and therefore would reject the idea the “Brain in a Vat” hypothesis. Another reason why it is discarded is due to Russell’s best hypothesis. This is the idea were, we cannot categorically prove that there is an external world, but it is the best explanation for the regularity and consistency in the universe. Because of this, Russell would argue that we are fairly safe in assuming that there is an external world. Furthermore, the science behind the “Brain in a Vat” hypothesis is pseudo-science. It is highly unlikely that we could ever create a substance which could support a brain, let alone understand the brain enough to stimulate it correctly to create a consistent external world. As a result, the “Brain in the Vat” hypothesis does not provide a substantive alternative to an external world, and therefore should be rejected.

But does the “Brain in the Vat” hypothesis truly provide the strongest case for scepticism about the external world. Or is there a thought experiment which could provide better support? I would argue that a stronger argument could be made by a VR experiment which could expressed as the following;

1. We are able to create a visual world within VR. This creates the same visual stimulation as the external world.

2. Other technology can be incorporated into this to engage our other senses in this new world. For instance, the use of pressure suits or incorporating sense of smell.

3. Eventually technology will develop so that there is no difference between the new world and the external world.

4. We may eventually forget there is an external world and that the new world is an external world.

5. This seems plausible based on our current understanding of science. However, it poses the exact same problem as the “Brain in the Vat” hypothesis.

6. Therefore, there is some hypothetical possibility to suggest that the external world is merely an illusion.

How does this argument deal with the objections against the “Brain in the Vat” hypothesis? To start with, it doesn’t deal with the problem of infinite regress. It is still possible that the world which put us into VR was also a VR world and continues going back. However, it could be argued that the thought experiment doesn’t need to deal with this. The argument isn’t suggesting that there is external regress. Infinite regress is merely the example being taken to the extreme. It is only at this extreme that the argument doesn’t work. When considering if the external world is a true representation of a different world or whether the external world doesn’t exist, at a maximum there only needs to be one separate world, not multiple. This is not a causation argument. It is an epistemological one.

This may not be a convincing argument for some. However, what the argument does deal well with is the pseudo-science of the “Brain in the Vat” hypothesis. In the hypothesis, it relies on us being able to develop a substance to keep a brain alive, developing sufficient knowledge of the brain to know how to stimulate it and then developing a computer to fulfil the task. Science is no where near being able to do this. In contrast, virtual reality is something that has already developed. We can already create new visual worlds and have already started to create “4D” experiences with other senses. As a result, the thought experiment provides a better hypothetical scenario which is more attainable and therefore provides a stronger argument than the “Brain in the Vat” hypothesis.

Finally, the thought experiment goes part way to challenging Russell’s “Best Hypothesis” theory. This is because it provides a more rational explanation to the “Brain in the Vat” hypothesis as it is more scientifically attainable. On top of this, it provides an explanation for why the world has continuity and consistency; because it was designed in a similar way to a VR game. Despite this, Russell’s theory is stronger than the thought experiment as it is a simpler explanation and therefore (according to Occam’s Razor) is the more probable one.

To conclude, VR can provide a stronger case for scepticism about the external world due to it being founded on technology that is already available today. However, it doesn’t persuade that there isn’t an external world due to Russell’s “Best Hypothesis” theory being a simpler theory and therefore more likely. Despite this, the VR thought experiment is still important, as it can be seen to strengthen the position of scepticism about the external world, and give it some support which otherwise it would not have had.

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