The reading that I will be exploring further is Moore's argument for an external world. Moore tries to show throughout his paper that all you need is a proof to show that there is, in fact, an external world. He identifies three conditions in which a proof is present. The first is that the premises have to be different from the conclusion; the second is that you have to know the premise, and the third is that the conclusion has to follow from the argument. A proof, in the sense that Moore is using it, is something that involves or implies the presence of people. Because of this, there is something very public about proofs in the way that he defines them. He believes that proofs are used to settle questions that we might have and that by following these guidelines you can create a rigorous proof to help solve the numerous riddles that plague our minds on a daily basis. In his article, Moore goes about asserting that he has done just that, created a rigorous proof to establish the existence of an external world.
The first question he poses is: can we prove that two human hands exist? Moore wants to say that he can prove the existence of two human hands by holding his own two hands up and observing them. His argument for an external world is a rather straightforward one. The argument is as follows: (P1) Here is a hand, here is another hand. (C1) There are at least two external things. This argument is an adequate one but is in need of the implied premise; "hands are external things," with this, the argument is valid. This argument is sound in the sense that all the premises are true, and valid in its form, yet it feels as though there is some kind of fallacious aspect in what it claims. Even those who may not be inherently skeptic could doubt the conclusion that follows from these premises. Because of this doubt, Moore lays out another argument involving an example of a rigorous proof used to settle doubt about a certain question that is in contention.
Moore's response, in regards to those who think that his first argument is not convincing enough to be a proof, is laying out another thought experiment concerning misprints. He says that we can imagine a case in which there is a question of if there were as many as three misprints on a page of a certain book. He uses person A and B, in which A states that there are at least three misprints and B doubts that there are any. Moore says that to prove that he is right, A could go to the page in question and point to the various places where there are misprints. The argument is as follows: (P1) Here's a misprint, here's another, and here is yet another. (C1) There are at least 3 misprints. Moore believes that if this is evidence of a sound proof, and we can accept that this argument is, in fact, a proof, and then it follows that his first argument of an external world must also be an adequate way to prove the existence of an external world. He believes this because if it is possible to be certain about the fact that there were at least three misprints on a page by observing the misprints, then it is possible to be certain that in this moment there is a hand here and another here by gesturing and then observing your hands, just as you gesture and observe that there are three misprints on the page of a book. I will be debating against this argument as a whole, including the notion that Moore does not, in fact, use a rigorous proof to argue his point, as well the idea that we cannot know our external world based on our own sensory observation.
The first idea I pose is not only a problem for the conclusion but for the argument as well. Although it is not blatantly obvious, this argument has a kind of epistemic circularity to its form. What Moore is trying to say is that because there is a hand here and another here, there is an external world. But, to be able to know and establish that there is a hand presupposes that there is an external world in which it exists.
My Argument:
(P1) If Moore's argument is epistemically circular, then its premises presuppose its conclusion.
(P2) Moore's argument is epistemically circular.
(C1) Therefore, its premises presuppose its conclusion.
(P3) If its premises presuppose its conclusion, then Moore's argument for an external world is not a valid and rigorous proof.
(P4) Its premises do presuppose its conclusion.
(C2) Therefore, Moore's argument for an external world is not a valid and rigorous proof.
Because of this presupposition of the conclusion, the argument is epistemically circular. In Moore's world, his hands must exist on some platform, this platform being the external world. If his hands can only exist if there is an external world, then the first premise about the observation of his hands is completely dependent on the conclusion that there is an external world. In turn, not only can we claim to know the argument is true because it is epistemically circular, but as a result, the rigorous proof requirements he is trying to convince us that this argument follows, come in to question. We have reason to think that Moore did not in fact set up an example of a rigorous proof to prove the existence of an external world. We should think this because to qualify as a rigorous proof the premises must be different than the conclusion. Whereas in his argument for an external world, the premises are dependent and thus similar to the conclusion, consequently discrediting his conviction in his argument that he does, in fact, adhere to the proof guidelines. In summation, a proof cannot be thought to be rigorous if it establishes a convincing conclusion through the use of premises that are contingent and therefore similar to its conclusion.
Moore would respond to this objection by saying that there are cases in which those who have no presupposed knowledge of an external world can observe their hands and prove that there is an external world, such as the case of toddlers. For example, when a toddler looks down and sees their hands, they can come to know that they do in fact have hands, yet the idea that they can know there is an external world based on this observation is too complicated for them to understand. If toddlers can show proof of the existence of their hands without the need to be aware of the existence of an external world, then it is not the case that you need to know the conclusion to know the premises in Moore's first argument of an external world. In addition, he would strongly reinforce that his premises are distinctly different from his conclusion, the existence of hands and the existence of an external world are entirely separate, and even more basically the existence of two human hands existing at this moment and having a hand here, and a hand here, are not dependent on each other in the slightest. Moore would argue vehemently against the idea that his proof did not satisfy his three conditions because the premise he adduced, in his proof, was vastly different than the conclusion that he was able to draw.
Moore would then reiterate the proof he lays out in his second argument concerning the misprints. In this case, you do not need to know that there are three misprints to establish the premise that they exist. Since he concluded that both argument A and argument B were so similar in that they must both be proofs, it would follow that if argument B was not epistemically circular then argument A must not be either, because it follows the same form. According to him, the premises are different than the conclusion, and the existence of your hands can be known through your senses rather than through first establishing the existence of an external world, just as you do not need to know that at least three misprints exist to prove that there are at least three on a page, rather all you need is to gesture and observe that they do exist.
My response to these claims is that when thinking about this idea of epistemic circularity we must argue in terms of justification rather than knowledge. Yes, a toddler may not have the intellectual capacity to know that there is an external world, but we should think that there is reason to believe that they have justification to believe that there is. Because of this, it remains that the argument is still in fact epistemically circular because even though there may be those who are not cognizant of the notion of an external world, there is still reason to believe that an external does exist independently of their ability to recognize it or not. In addition, as far as the misprint argument goes, it is an argument that someone may actually make without necessarily knowing the conclusion. You can observe there are misprints on a certain page of a book, and prove that there are, without prior knowledge of the book already containing at least three misprints. Whereas in the external world example it seems that you must already be convinced of the conclusion to accept what the premises claim, because the thought is that for you to be able to observe your hands then there must be an external world in which they both exist.
The second objection I bring is in the form of a truly inherent skeptical school of thought and reflects the Cartesian genre of skepticism. That is, that there may be a metaphysical possibility that our experiences while we are awake and while we are asleep are not so different, and in fact indistinguishable. This argument against Moore is the idea that we cannot necessarily know that there is an external world based on our own physiological senses. At this point in time, when I am looking at my hands, I may believe that I am awake and that there exists a hand here and another here, yet for all I know I could be dreaming instead. If I am in fact dreaming then my sense are deceiving me, and thus are not trustworthy.
My Argument:
(P1) If there is a possibility that our senses could be deceiving us, then we cannot trust the observations we make about our environment.
(P2) There is a possibility that our senses could be deceiving us.
(C1) Therefore, we cannot trust the observations we make about our environment.
(P3) If we cannot trust the observations we make about our environment, then Moore's proof of an external world through the use of observation is not sufficient reason to believe there is proof of an external world.
(P4) We cannot trust the observations we make about our environment.
(C2) Therefore, Moore's proof of an external world through the use of observation is not sufficient reason to believe there is proof of an external world.
From this, it follows that if my being awake is dubious, then the knowledge that I think that I have used to come to know the conclusion that there is, in fact, an external world, is also questionable. In addition, if I am in fact dreaming when I look at both of my hands then it is the case then there is no proof of an external world but rather an internal world in which my hands exist. The idea is that an external world exists independently of the mind, but if I am dreaming then the existence of my hands is within my mind, not existing separately from it. This argument gives us sufficient reason to think that Moore cannot deduce, from the observation of his environment that an external world exists. This is due to the possibility that our senses could be deceiving us, ergo we cannot make reliable observations about our environment to prove that there exists an external world.
Moore would respond by saying that when we are asleep we cannot know or recognize that we have hands. Because we cannot know anything for certain when we are dreaming, then it follows that we cannot prove that there is not an external world. In addition, Moore would say that there are some cases in which we can know things that we can't necessarily prove. Because of this, the dreaming hypothesis presented by Descartes holds no real threat because we can reasonably recognize that we are awake because of what we see, the sounds we hear, or things we taste, even though we cannot necessarily prove it. Moore would go on to say that there are reasons to think that he is awake rather than asleep because he can show evidence of his being awake, although he cannot necessarily prove that he is not dreaming. He would conclude that the premises he lays out within his argument are things we should be able to know, rather than things that we should take on faith. He would end the response by saying that this lack of a definite definition of a proof, may lead skeptics to continue to doubt his own proof of an external world; in which he wants to argue that there shouldn't necessarily be a reason to doubt his rationalization. His reason being that it is just a fact of life that there are some things you know, and come to know, that you can't necessarily prove but are nonetheless true.
Moore lays out an argument for an external world that he believes is a rigorous proof through the observation of his own two hands. He believes that in addition to this proof there is support for this type of proof through his argument of observable misprints. I conclude that the proofs he has given are unsatisfactory and not conclusive in proving the existence of an external world, as well as in establishing a rigorous proof. Moore's proofs leave gaping holes in the argument as a whole and do not directly answer the question of the existence of an external world in detail. Although the argument is seemingly valid and sound, the premises are based on the conditional truth of the conclusion, and the conclusion in an argument cannot ever be necessarily known or claimed. Because of this definition of epistemic circularity we can see that Moore's argument is in fact epistemically circular, ipso facto, we cannot reliably conclude from this argument that there is an external world based on the observation his hands.
Finally, because of the uncertainty of our own perceptual experiences, Moore's proof through observation is not sufficient reason for us to believe that we are not in fact being deceived by our own senses. In addition, even if we may be able to tell that we are awake versus asleep, there is reason to think that there may be some non-zero chance that our knowledge of being awake versus being asleep may be indistinguishable. For this reason, as well as the notion of epistemic circularity, there seems to be a lack of definite knowledge to prove that an external world exists through the observation of one's own extremities. Because of these reasons, we should think that Moore does not use a rigorous proof to give us sufficient reason to believe in the existence of an external world through observation.
