According to Duncan Pritchard’s chapter about radical skepticism in “What is this thing called Knowledge?” there is no way of knowing if our brains are stimulated in a way to make our experiences seem normal. Therefore, Pritchard concludes that if we are unable to know if we are victims of skeptical hypothesis, then “we are unable to know very much at all.” (Pritchard, 170)
A modern day example of this hypothesis is demonstrated by the movie The Matrix. In the movie, a man’s brain is in a vat of nutrients and is being fed computer-induced experiences that seem to be real. Since he is being controlled in a vat, there is no way of knowing if any of his interactions are real.
An extreme example is a world that lacked physical objects except for yourself and an Evil Genius, who controls all of your experiences. In this case, your beliefs would be mistaken because “your experiences represent there to be an external world of physical objects (including tour body.)” (Brueckner) Many philosophers deny the possibility of this hypothesis because they fail to believe in a matterless world.
So, we cannot conclude that we know anything unless we are able to identify being a victim of a skeptical hypothesis, such as being in a brain vat. However, if our experiences would be indistinguishable in either case, then it is impossible to know if we are being deceived or if we are in reality.
No matter how many philosophers attempt to refute the hypothesis, it always seems to come back to the idea that we cannot distinguish an artificial experience that is designed to completely replicate a real one.
Since it is impossible to conclude that “I am not in a large vat being fed experiences that are designed to deceive me.” (Pritchard, 171) Thus, I do not know if anything that I am doing is true. Am I a college student at Emory University? Do I have the ability to type this post? Is there a book open in front of me? Or am I deceived by these appearances and experiences that seem so real? I wonder if I can be under an external power that controls my ability to experience the world.
Other Sources:
Brueckner, Tony (2004) ‘Skepticism and Content Externalism’, Stanford Encyclopedia of Philosophy
http://plato.stanford.edu/entries/skepticism-content-externalism/
It seems you have chosen to completely side with a radical skeptics point of view. Pritchard puts forth the idea that radical skepticism is not a philosophical thought but merely a way to counter those in pursuit of knowledge. Too much skepticism when trying to define examples of knowledge is dangerous. Skepticism should be used as a tool to challenge the truth-value of an argument an whether or not there is knowledge in certain situations, but too much of this can create a world where we know nothing at all. Why do you believe that this may be the case?
I am kind of torn between how much skepticism is “too much” as mentioned by Donald previously. How can we limit an amount of skepticism? My point is – do you think skepticism is a slippery slope and will always lead to the conclusion that “we know nothing” or is it possible that it can merely be utilized as a tool for challenging the truth-value of an argument?
Although this point is radical, it is a valid argument. If we can’t prove that our experiences are real, then how can we be sure that we have real knowledge of anything. I don’t believe that too much skepticism is dangerous. I think that it is possible that we can know nothing at all according to this argument, but I don’t go around everyday thinking about how it is a possibility that I don’t know anything. This argument is interesting to think about, and is valid enough to be true, but I am not sure if I believe the argument in my daily life.