You imagine that you know yourself better than anyone else in the world, but do you really know who you are?

Questions like this are what Descartes discusses in his two meditations, where readers are led to question everything. In his first meditation, Descartes focuses on doubt. To do so, he states how he must forget everything he has ever known “and start again from the foundations” (Descartes, 1). The overall focus of the first meditation is that Descartes talks about a “malicious, powerful, cunning demon” that deceives him (Descartes, 3). This demon inputs dreams that trap Descartes’ judgments and make us wonder: if  when we are dreaming, are we just dreaming while we’re asleep, or is all of life a dream?  I suppose that it is possible that a demon can be controlling our lives, but I don’t see why some demon would be doing this.

It is fair to say that one is doubtful of these claims. If one believes this theory, in order to have a justified true belief, S must contain strong evidence that supports such P. I suppose that this situation could be possible in another world, but there isn’t much to any evidence that supports this idea in this world.

Descartes goes onto his second meditation and discusses the human mind. He starts off stating that “everything [he sees] is fictitious. [He] will believe that [his] memory tells [him] nothing but lies. [He] has no senses. Body, shape, extension, movement and place are illusions. So what remains true? Perhaps just the one fact that nothing is certain” (Descartes, 4). He, next, chooses to discuss the senses and how valid they are by focusing on a piece of wax. The senses led to the mind drawing conclusions that the solid and liquid wax forms were the same, but this is not the case. In addition, if you were holding a piece of ice, you would conclude that the ice is cold because that is the answer you get from your sense of touch/feel. According to Descartes, we don’t really know that the ice is cold (Pynn, 1-2); our senses cannot be trusted at all times because there are instances when they can fool us. How do I know that I am actually feeling the back of my desk chair right now, or my fingertips pressing against the keyboard? This could all be a lie.

Bostrom’s essay about post-human simulations contradicts Descartes views on the mind. Where Descartes argues that the mind is the only thing that truly exists, Bostrom discusses the possibility of our minds possibly being run as an ancestor-simulation “rather than among the original biological ones” (Bostrom, 1). How do we know whether or not this is the case? One can wonder for all of his or her life, but will there ever be evidence to prove this is the case? Would those in control of our minds ever allow us to notice such evidence? Therefore, we cannot know that this is the case. Also, our “thoughts” would not truly be our own if we are being controlled by others, so is our mind even uniquely ours? The justified true belief account requires evidence and it is unclear if we will ever have that. I have to see Bostrom’s theory as a possibility because who knows? In another possible world, this could be the case, or even in our own world. We wouldn’t know any different unless those controlling us made us aware.

For all we know, we could all just be brains in vats being controlled and none of these experiences of life are reality. Like the Doubtful viewpoint in the first meditation, “this discovery makes me dizzy…” (Descartes, 2)

Other Sources:

Handout 2: The First Meditation (Professor Geoff Pynn): http://www.niu.edu/~gpynn/322_H2.pdf

I thoroughly enjoyed reading Descartes’ ideas and seeing him struggle to try and rap his mind around these tough questions. I honestly agreed with a lot of what he argued but in this blog post I would like to try to play Devils advocate a tiny bit, even if I don’t actually believe what I am writing. I wanted to start with Descartes’ major idea in these Meditations, “I think, therefore I am.” It seems logical enough especially after he goes into detail about this particular belief. However, one question popped into my head after mulling over Descartes’ argument for a while. When exactly do humans first acquire the ability to think? Or even more so when do humans first become conscious of who they are or what they are?

Like any good member of the millennial generation I took to the Internet to answer this question. A quick Google search displayed a wide variety of results, one of which I have shared with you all below. As I had originally suspected there is a period of human life where we are incapable of thought and that is when we are in our mother’s uterus. The question I would ask Descartes is that if thought was the only evidence he could find for his existence, does that mean a baby who is not yet capable of thought does not truly exist? It is an interesting thing to think about, and I would argue that that unborn baby does exist all though its brain is not fully formed yet, and it is not even close to being able to think of these philosophical questions. I understand that Descartes is using thought as pure evidence that we are in fact something, but it does still beg the question are we something before we can think?

Building off that, I would also like to talk about Descartes’ hypothetical idea that instead of a loving all-powerful God there is a sinister controlling being that could be deceiving us at every point in our lives. I agree that this could possibly be the case or at least there is no proof that this is not the case, however I think Descartes overlooks something that also relates to his hypothesis “I think therefore I am.” If this evil being really was all-powerful and able to control what we see and believe couldn’t he control our very thoughts too? What is so powerful about Descartes’ idea of thinking if our whole consciousness could be entirely controlled by a malevolent force?

Even the very process of thinking about these big questions could be controlled by this evil and could be leading us in a completely false direction. And even more so, if our very thoughts were completely controlled by something else does that really count as thinking? It seems like the very idea of thinking revolves around being independent and free to explore your own mind. If some other being in fact controlled our thoughts I am not sure we could consider them thoughts. And if that is the case, that we can’t actually say for sure that we are thinking, Descartes whole proof of existence falls apart.

Sources:

http://www.scientificamerican.com/article/when-does-consciousness-arise/?page=1

After reading Descartes meditations, it seems clear: we can think, therefore there must be an ‘I.’ In other words, if we are doing anything, thinking, doubting, hoping, the fact is we are. We exist. What I did think was interesting in his argument in the beginning was when he said that we must doubt something that even has a small chance of being untrue. He mentions that his senses sometimes deceive him, as in dreaming. While extreme, this concept is essential.

On a slight tangent, with modern day technology and research we can corroborate this, but even in every day life. Elizabeth Loftus wrote in the 1980s about false memories.

http://www.slate.com/articles/health_and_science/new_scientist/2013/09/elizabeth_loftus_interview_false_memory_research_on_eyewitnesses_child_abuse.html

This means that while we think we remember something, it did not in fact happen. So if our senses are really that unreliable where we think we have gone somewhere or done something that actually has never happened, then who is to say we aren’t brains in a vat being manipulated by bored scientists?

Descartes also mentions that there are some things that, whether dreaming or awake, are always true such as two plus three equals five and a square has four sides, a triangle has three, etc. However, if we truly are brains in a vat, isn’t it entirely possible that these truth elements could be altered? Couldn’t someone make us think that 2 + 2 = 5, just as we now think that 2 + 2 = 4?

Next, Descartes differentiates between the soul and the body. The body, he argues, is the structure of bodily parts (arms, hands, etc.) while the soul is where sense-perception and thinking occurs. While I don’t doubt that there must be some sort of location where thinking and perceiving occurs, I can doubt that I have a body. Again, we could just be brains in a vat where someone makes me think that I have a body that moves.

Thomas Hobbes responded to this separation of thought and body with, how can the body be separate from thinking as you need thinking to move the body? He says that “the mind is nothing more than the movements of various parts of an organic body.” These things Descartes describes as two separate entities, and yet, they cannot exist alone without ceasing in existence. This brings up for me a question of what it means to exist or be alive, but seems to be a totally different problem. Are we really living if we are brains in a vat? Aren’t we just a sort of zombie if someone is telling us what to think?

Moore wrestles with similar issues of what we can actually be certain. He says that there is no way to know for certain that he is not dreaming when he thinks that he, for example, is standing up. But he then argues that the sensory memories of the recent past “may be sufficient to enable [him] that [he] is not dreaming.”

He goes further to say that it is logical to argue that he may be dreaming right now and that he is dreaming would not be self-contradictory; but saying that he can’t be having both all sensory experiences and memories that he has, and be dreaming, is illogical and self-contradictory.

I believe that you could be dreaming and have sensory experiences and memory. Just as we can remember actual events, we can remember what has happened in a dream and sometimes the two blur. So couldn’t our memories of a “sensory experience” be just of a dream?

After reading this, I begin questioning whether I am actually a body and not a brain in a vat or living in a computer simulation, because as far as I can tell, there isn’t a way tell. Descartes and Moore reiterate one common conclusion for me: I am, but I also am certainly uncertain.

Hobbes: http://www.earlymoderntexts.com/pdfs/descartes1642_2.pdf

Nick Bostrom’s essay “Are You Living in a Computer Simulation?” brings up the intriguing, although rather mind-boggling concept of super-intelligence with the simulation argument involving post-human civilizations. His theory is laid out using seven sections, each of which builds off the idea of post-humans running ancestor simulations, and the fact that there may be a chance that we are actually a part of these simulations.

As a brief recap, the general premise of Bostrom’s theory stems from the fact that humans have made tremendous strides in the realm of technology, and our previous generations have invented an enormous technological infrastructure. This leads to the humbling implication that the technology we have today is rather limited and will be considered simple and quite basic in comparison to what our posterity down the road will have in their lifetimes. Therefore, future civilizations will have enough technological development to aptly run ancestor simulations.  Bostrom then arrives at three conclusions, and hypothesizes that at least one of them must be true.

Upon an initial reading of Bostrom’s work, one may somewhat understand where he is coming from and maybe even agree with his theory. However, upon a deeper analysis, more questions seem to arise, and such was the case with my experience while reading his piece.

I somewhat disagree with Bostrom’s idea that we are living in a simulation.  First and foremost, Bostrom never formally defines what exactly he means by “simulation.” Essentially, a simulation could be anything, and by not defining what he intends it to be, Bostrom’s theory comes off as confusing.

Another possible, although kind of minor critique is that fact that Bostrom assumes too much. It seems to be implied that if people are in fact being simulated, then they are unaware of it, meaning the simulators do not tell their subjects what is happening. By the protocols of modern science, this is unethical, leading to the assumption that these super-humans of the future are themselves unethical people.

Going off of the unethicality issue, it seems rather illogical to me that a civilization so advanced that it can run these simulations has no legal or moral protections established for the living subjects it is manipulating. If we are, in fact, in a simulation, then it is safe to say that our simulators create everything we experience, both good and bad. While this may not be a problem for the good things, this also means that our simulators are responsible for all the crimes, murders, etc. that we may face. If the legal system of this future is anything like our current one, then all the aforementioned things should be illegal, but if our simulators are exposing us to them anyways, it can be assumed that morailty is simply unconsidered. While this may or may not be a major flaw in Bostrom’s theory (depending on how you view it), I still believe it’s worth pointing out.

Another flaw I found with Bostrom’s theory is the fact that it is circular and to some extent, self-destructive. To start off, it can be said that the people running the simulation are incredibly intelligent and efficient – more so than us – because they are able to run these simulations in the first place. With this in mind, the whole theory speculates about a world higher than ours, while the whole simulation itself seems to suggest that if we are living in it, then we would have no way to know anything about such a higher world and what its people are like, what their intentions are, etc. Basically, the supposition that we are living in a simulated world leads us to believe that we can’t trust the assumptions, which led us to our first conclusion, making it a very self-contradictory situation and therefore semantically meaningless.

Taking all of the aforementioned assumptions into account, it can be argued that Bostrom’s hypothesis violates the principle of Occam’s razor. Occam’s razor is essentially a principle that states that between multiple hypotheses, the most reliable one would be the one that includes the fewest assumptions. Therefore, other somewhat similar theories regarding higher intelligence may technically be more reliable than Bostrom’s, provided that they include fewer assumptions and provided that we actually take them into account.

Sources:
http://en.wikipedia.org/wiki/Occam’s_razor
http://www.simulation-argument.com/computer.pdf
http://www.longecity.org/forum/topic/3402-against-the-argument-that-we-live-in-a-simulation/
http://users.digitalkingdom.org/~rlpowell/rants/simulation_errors.html

How do we know that we do not know?

At first glance, meditations 1 and 2 by Descartes seem like the foundation of a skeptical argument. However, when analyzed at a deeper level, his argument is not as much of a skeptical approach as it seems.

To begin, Descartes offers the dream, deceiving God, and evil demons arguments, each building off the premise that our senses can be deceiving. Although Descartes poses a strong argument, each situation can be evaluated for its weaknesses. Firstly, even though dreams can resemble much of what one sees in the real world, there are still notable differences. Seen in the movie Inception, the biggest difference seen in the dream world is a lack in continuity. Therefore, although not obvious, it can be argued that it is possible for one to know that he is not dreaming and in fact present in the real world.

When considering Descartes’s deceiving God, and evil demons arguments, it is a very far possible world. It is just as likely, if not more, that these two things do not exist. Due to the fact that they are very far possible worlds, Descartes does not actually give sufficient evidence to prove that these possibilities are true.

Descartes says that some people or things may be more deceived. However, consider the process of deceiving. According to the JTB account of knowledge and many others, in order to know that one is deceived, one must first believe he is being deceived, and one must also be justified in having that belief.  In order to fulfill these requirements, one must first realize that he is being deceived. Once one realizes that he is being deceived, is the deception still a deception? When applied to the broader term of skepticism, can one still be a skeptic if one realizes that the entire world around him is a deception?

This argument however, leads into Descartes’s second meditation. In this meditation, the hopeful seems to make a more powerful argument. When arguing with the doubtful skeptic, the hopeful says: “for if I convinced myself of something then I certainly existed.” (4) Take for instance, that one was actually a brain-in-a-vat. Even if the brain was being stimulated by other sources, the brain itself does actually exist. Therefore, it could not possibly be true that nothing exists. If one is able to have sensory intake, it is very possible that the intake itself is a deception; however, the thing that is taking information, the “I” in the case of Descartes’s second meditation, must exist.

Descartes arguments seem to be very powerful in the questions that it stirs among philosophers throughout the ages. Although many aspects of his arguments, especially in the first meditation, can be used for a skeptical argument, it is very important to realize that that is not the sole purpose that Descartes is trying to convey. Descartes’s arguments should be used by philosophers, to be aware of the world and their knowledge of it, instead of rejecting it as a whole.

Other sources: “Important Arguments from Descartes’ Meditations.” http://www.anselm.edu/homepage/dbanach/dcarg.htm. Web.

What am I?

What is “I”?

These two fundamental questions that Descartes grapples with throughout his two meditations present the reader with some interesting logic to follow. I can agree with Descartes’ desires to re-lay his foundation of beliefs so as to have a more authentic base to build future knowledge upon. However, as he continues through his first meditation, the tone of doubt that permeates his logic made me ask a few questions:

1. Why is this alleged great deceiver, if there is one actually working against man and God, going through such great lengths to construct this idea of being alive? What would be the point of that?

2. If all belief is discounted based upon the abovementioned assumption by Descartes, then what is he looking for to “counter-balance the weight of old opinion”? (3)

I found the reasoning in the first meditation to be a bit too aggressive. To completely discount every belief on this quest for enlightenment seemed a bit too hasty for me. I’m of the mindset that our beliefs keep us alive. They’re the reasons we continue going through life. We believe that if we do certain things consequences whether desirable or undesirable will follow. This is the ebb and flow of life (in my opinion). If you don’t believe in anything what do you do?

The second meditation was a bit more rational because of the supposition that as beings we could believe at least one thing: We are thinking things that exist, comprised of doubts, understanding, affirmation, denial, desires, refusals, imagination and awareness. But this was the only thing Descartes was willing to believe beyond the shadow of a doubt. If this was to be his new foundation to build upon, what else was there out in the universe to believe? He had discredited everything else other than this singular notion.

I can understand and appreciate where Descartes is coming from with these meditations, but overall I found these two together to be a bit egocentric in the sense that it was focused so much on him. The only belief he allowed to exist at his core was the belief that he existed, and everything else, according to him, was a product of some great deception. What if someone else were to come to this same conclusion. Would both of them be right (they were each individually the only thing that existed and they each individually were just products of great deception in the mind of the other)? How could this be explained? I’m sure with the rest of the meditations Descartes’ logic is flushed out more extensively, but these are my first impression of reading him.

Nozick believes that in order to have knowledge, the belief needs to track the truth. In other words, for one to have knowledge, one must believe P, P must be true, and one’s belief’s must track the truth value of P.

For this reason, the casual account of knowledge must be false. The casual account of knowledge states that the fact that P is true causes S to believe P. However, think about a mentally ill patient who suffers from paranoia. Suppose this patient, without any proof or facts, believes that his mother is plotting to kill him; his belief is simply based on his impaired brain chemistry. Now, suppose that by coincidence, his mother very recently actually did begin formulating a plan to kill the mental patient. The mental patient’s belief would be true, however, the mother’s plan to kill him is not the reason for his belief. Therefore, P being true is not the cause for the mental patient’s belief.

So if the conditions: P is true, S believes that P, and the fact that P is true does not always cause S to believe P, is not sufficient to constitute knowledge, what is? Nozick believes that the solution can be found by adding to subjunctive statements. If P were not true, S would not believe P, and if P were true, S would believe P. If Nozick is right, the conditions for knowledge would look like this: P is true, S believes that P is true, if P was not true S would not believe P, and if P were true S would believe P. If these rules are applied to the mental patient example, it is clear that the mental patient does not know that his mother is actually plotting to kill him. If the mental patient’s mother was not trying to kill him, the patient would still believe that his mother was trying to kill him. It is evident that Nozick’s third condition for knowledge makes belief sensitive to the truth value of P’s falsity.

In the previous situation, if P was true, S would believe P. But that is purely by coincidence. Consider this situation:  There is a family with a mother, father, daughter, and son. The son is a compulsive liar and tells his parents that he is going to play tennis after school. The parents believe him, but the sister believes that the brother will not play tennis after school, but will do something else entirely. In this situation, P is true, S believes that P, and if P were false S would believe P, but if P were true she would not believe P.  In this case, the sister is correct – her brother is going to do something other than play tennis.  The sister’s  belief is not based on any supposition about the boy’s continual lying, however, but exists only because she did not hear the lie from her brother. If she had, then she, like her parents, would have believed that the brother was going to play tennis. Therefore, the sister cannot have knowledge. In order to fix the problem, Nozick created the 4^th condition, if P were true, S would believe P. With this condition, belief is sensitive to both the falsity and truth of P.

Nozick’s conditions make it so that beliefs track the truth value of P. Therefore, if knowledge can be defined by the conditions of P being true, of S believing that P is true, and of S’ sbeliefs tracking the truth value of P, then Nozick has successfully defined knowledge.

Disclaimer: It is not my claim that Nozick’s definition for knowledge is true; it is that if it is, then his conditions would constitute knowledge.

Duncan Pritchard talks about Contextualism in the 15^th chapter of his book, “What Is This Thing Called Knowledge.” Contextualism is this fascinating theory where the key to resolving the skeptical problem lies in recognizing that knowledge us a highly context-sensitive notion (Pritchard, 176).  Everything is relative to the statement said such as, shape, size, color, geography, etc. The idea of knowledge shifts depending on outside factors.

For example, the fact that a refrigerator may be empty has the connotation that it is empty of food. However, the refrigerator isn’t empty of air or light. Depending on what exactly you are thinking or to whom you are speaking to, the mind works differently. For me personally, I would think that the refrigerator is empty of the foods that I like. Another example that Pritchard uses is a table being flat. If a table is flat, there is a chance that there are no dents but that doesn’t mean there aren’t any air bubbles, bumps, or ridge. For me, a flat table can’t be made of wood because I think of glass when I think of a flat table and not the wood table in my backyard that gives me splinters.

My title is obviously from the infamous movie, Mean Girls. This movie is about four popular girls in high school that basically controlled the atmosphere of an entire school based off of their social status. But when using contextualism, what exactly makes a person popular?  In the area that these girls lived in, we can start by the physical and monetary backgrounds. All four of them are beautiful and were able to afford many expensive items. What defines them as being beautiful? Where these girls were from, being skinny and wearing skimpy clothing is what made them stand out from all the other people. But now if we were in Somalia, the women who are beautiful are those who keep themselves conserved in full body robes and headpieces and were able to dance well with a good layer of fat on them. These same four girls wouldn’t even be looked at twice in a positive way if they lived in Somalia. Contextualism is a valid theory because saying someone is beautiful really does depend on outside factors. In this specific example, geography plays a huge role when describing the adjective, “beautiful” and how it ties into popularity.

Now just because I agree doesn’t mean that there aren’t other arguments against this theory. The first is skepticism, and the second is Mooreanism. Both skeptics and Mooreans maintain that the standards for knowledge do not shift. (Tim, ‘Contextualism in Epsitemomlogy’). For skepticism, there is no support that for everything that you do in the world you live in and there is also no support that you aren’t in a deceived world. Skepticism has nothing to do with outside influences like contextualism and neither does Mooreanism. Mooreans often take a different tack and try to show how we can know the denials of skeptical hypothesis even though we are unable to tell such cases apart from counterpart non-deceived cases(Pritchard, 175).

Contextualism is really just a response to the skeptical problem in a way that is affected by outside influences and circumstances. There are many factors taken into consideration when making an argument. An argument about something in one topic may not work somewhere else with someone else. Everything is relative and knowledge is a radically context-sensitive notion. I agree with contextualism and I believe that almost everything one person says must be said to a certain audience to be valid.

Other Sources:

Contextualism in Epistemology (Tim Black): http://www.iep.utm.edu/contextu/

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/

Chapter 15 of “What Is This Thing Called Knowledge?” by Duncan Pritchard presents a type of skepticism known as radical skepticism.  This idea holds that it is impossible to know much of anything at all (Pritchard, 169).  Most philosophers agree that this form of skepticism is not a philosophical thought, but a way to challenge those in the pursuit of knowledge; a methodological form, which someone uses in order to try and prove that his or her knowledge presented, is skepticism-proof (Pritchard, 169).  Skepticism is a necessary tool in assessing truth-value of an argument, but too much of it creates an impossible task and thus should not be overly used by those trying to uncover knowledge.  Instead of having the mindset that anything could in fact be wrong or misleading, I’d lean towards the contextual response to radical skepticism, stating that different contexts set up different epistemic standards (Black, http://www.iep.utm.edu/contextu/).

The amount of skepticism necessary depends on the context of the situation at hand.  Using an example similar to that of Pritchard, a scientist looking at her tools does not need the same amount skepticism in determining the effectiveness as a person who is preparing herself a snack in the kitchen.  The scientist would need more skepticism in investigating her belief that her microscope and like equipment are in the right condition for her experiment whereas the person looking at her utensils would not need to use as much skepticism in the evaluating the belief that her kitchen tools will be able to make her sandwich.

Although there are situations that require a more in depth evaluation that are labeled high-standard contexts, and thus the use of skeptical arguments are highly regarded, contextualists believe that most contexts have epistemic standards that are relatively low.  And in these low epistemic standards, the necessity of skepticism is not very urgent (Black, http://www.iep.utm.edu/contextu/).   In this sense, we can have cases of knowledge that are free from issues of that radical skepticism brings up without taking the idea of skepticism in other situations.

On the basis of contextualism, one can still use the closure principle which is often times a good way to determine if the argument is valid or invalid.  Contextualism allows for arguments of low-standards to use the closure principle while arguments of high-standards must look further into the beliefs using skepticism as a tool in this process.

One main counter to the contextualist view is that radical skepticism does not need high standards in order to come into play.

“…the skeptical claim is that we have no good grounds at all for thinking that we’re not the victims of skeptical hypotheses, not we have good grounds but the grounds we have aren’t good enough” (Pritchard, 178).

In this argument, there are no standards when it comes to radical skepticism, because no grounds for an argument are good enough.  This counter-argument shows just how radical this much skepticism is.  The idea that someone can’t really be sure of anything is a little frightening and could leave a person with a very unstable mindset.  It’s also a very frustrating take; that nothing could be proven to be valid because there is always room for something crazy; for example, that our brains are floating in a vat and being controlled by outside forces.  Of course, like what was brought up at the beginning of the chapter 15, radical skepticism is not really a position philosophers take, but just a challenge that must be overcome to arrive at knowledge (Pritchard, 169).

So the main questions that remains is when do we use skepticism? And when does skepticism become excessive?  The contextual argument holds that there are times (many times in fact) when skepticism is not necessary and therefore one can use the closure principle and thus find relatively easily if the argument is valid or invalid.  Within this contextual practice, there is room for skepticism but only when absolutely necessary (high-standard situations).  Knowledge comes in varying degrees, so it seems prudent that different methods be used to analyze an argument depending on the specific degree of that argument.

Other Sources:

Black, Smith. “Contextualism in Epistemology”.  Internet Encyclopedia of Philosophy.  https://owl.english.purdue.edu/owl/resource/747/08/