PAPER #1
In this paper I am going to argue that conclusive proof is not necessary for knowledge
because according to Locke there is no such thing as absolute certainty and absolute certainty
would lead to conclusive proof.
G.E. Moore has made an argument. The argument is that he sees one hand and sees
another hand. He knows that he is seeing the two hands; therefore two human hands exist.
Moore wonders if he could apply this proof of the external world to prove all kinds of external
world objects. In order for Moore to apply this proof to all kinds of external world objects he
must find out what a proof demands. Moore develops the answer for this. Moore says that a
proof must follow three conditions. The first condition is that the premise of the proof must be
different than the proofs conclusion. The second condition is that we know and don’t just
believe that the premise is true. Finally, the third condition is that the conclusion must follow all
the premises. Once Moore established these three conditions he found that his proof meets all of
the conditions. Moore then asks if there are any other conditions for rigorous proof. He
concludes that if there are any other conditions he does not know what they are. Moore then
asks himself if he is dreaming. He discovers that he doubts a proof that leads to absolute
certainty of certain types of propositions is possible. He admits that his premise cannot be
absolutely proven since he cannot absolutely prove that he is dreaming. So, in order for him to
give conclusive proof he must give evidence for why he thinks he is not dreaming. Moore
doesn’t think he will be able to tell what the evidence is even though he has good reasons that he
is not dreaming. Moore concludes that conclusive proof is not necessary for knowledge. This
brings up a good question. Is conclusive proof necessary for one to have knowledge?
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Conclusive proof is not necessary for knowledge. According to John Locke a person
does not need to be absolutely certain of anything in order to have knowledge. To be absolutely
certain of something there must be nothing to go against your proof. Conclusive proof means
that someone can prove that their proof has no other conditions that would lead to their proof
being false. So, actually conclusive proof would mean that a person is absolutely certain that
their proof is not false. Locke believes that the only source of genuine knowledge is sense
experience. It is the probability and likelihood of these sense experiences that leads to your
knowledge of something. Locke says that there is no such thing as absolute certainty because
sense experience doesn’t provide certainty. He also says that reasoning based on your sense
experiences creates and inductive argument. An inductive argument is an argument which
produces the thought that the premises provide reasons supporting the probable, not certain, truth
of the conclusion. This would lead to the conclusion that conclusive proof is not necessary for
knowledge since the premises don’t have to provide absolute certain reasons to support the
absolute truth of the conclusion.
Decartes would argue that conclusive proof is necessary for knowledge. Decartes
believes that a person needs to be absolutely certain that the conclusion is true in order for one to
gain knowledge. Decartes thinks that beliefs plus justification equals knowledge. In order to
justify your beliefs one would need to find evidence and reason for their beliefs to yield
knowledge. Decartes also believes that sense experience is unreliable and an inadequate means
of knowledge. If sense experience is unreliable then it would not provide absolute certainty.
Since, Decartes believes that one must be absolutely certain to have knowledge. Since, Decartes
says that absolute certainty doesn’t exist, so one does not have any knowledge because absolute
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certainty yields knowledge. Therefore, according to Decartes, conclusive proof is necessary for
one to have knowledge.
In conclusion, John Locke agrees with Moore’s conclusion because sense experience
creates an inductive argument, which means that the premises do not need to provide absolute
certain reasons that the conclusion is true. In contrast, Decartes believes that you must be
absolutely certain that your premises provide reasons to make one’s conclusion true. I agree
with Locke because I believe that it is the likelihood of your experiences that yields knowledge.
One does not have to absolutely certain that the premises could yield reasons for one’s
conclusion to be false. I don’t agree with Decartes because absolute certainty doesn’t exist.
Since, many people have knowledge about certain things, then, one doesn’t need to be absolutely
certain to be knowledgeable. One just needs to know and believe that the premises can yield a
true conclusion.
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PAPER #2
In this paper, I will argue that Moore has not proved the existence of his two hands
because his argument assumes what he is trying to prove. He is guilty of an Epistemic Circle, or
a circular argument.
Moore’s essay “Proof of an External World” argues that he can prove the existence of
external things by holding up each of his hands, gesturing, and saying, “Here is one hand” and
“Here is another.” Moore bases this on three conditions for a rigorous proof: (1) The premise is
different from the conclusion; (2) The premise is something that he knows and does not just
believe; and (3) The conclusion follows from the premises (197). Unfortunately for Moore, he
has not satisfied two of these three conditions. The main problem with his argument is the
relationship between (1) and (3).
Moore states that his premise is certainly different from his conclusion because his
conclusion is a simple statement (“Two human hands exist at this moment”), and his premise is
much more specific than that. He claims that his premise is more specific because in addition to
saying, “Here is one hand, and here is another,” he shows his hand and makes certain gestures
(197). He approaches his proof as an empiricist, but fails to convince a skeptic. In order to put
forth his first premise, Moore assumes his conclusion, thus forming a circular argument. How
can he know that his hands were there without assuming that there are external objects? This is
his argument.
1. Here is one hand. (Gesture)
2. Here is another. (Gesture)
3. Hands are external objects. (By definition)
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4. External objects exist.
Moore is basically saying that we know there is an outside world because we know there is an
outside world. He assumes the existence of external objects to prove that external objects exist.
Descartes’ argument shows that if you don’t know that there are external objects, then you don’t
know that you have hands.
Moore admits that he cannot prove his premise, because he cannot prove that he is not
dreaming. The principle of his argument hinges on his statement, “I can know things, which I
cannot prove” (199). So instead of saying that he believes or thinks that his hands are where he
gestured, he asserts that he knows it. He even goes so far as to suggest that it is absurd to
suggest otherwise. This seems a bit dismissive, but this condition is critical to his argument. If
Moore were to use “believe” or “think” in place of “know” in his argument, it would be a much
weaker argument and would likely fail. He insists that he does know it as clearly as he knows
that he is standing up and talking – a common sense notion. However, common sense is not the
equivalent of knowledge. It is also wrong to assume that certainty is knowledge. There are
numerous examples to prove this point. At one time, people were certain that the earth was flat.
In addition, we’ve all heard someone say at one time, “I thought I knew…” Furthermore,
Moore’s actions are based on the information that he has received through his senses, yet he
dismisses the idea that he may be dreaming. But Moore does nothing to prove that he is not. He
says that he has conclusive reasons to assert that he is not dreaming, but he cannot prove it. This
is ad ignorantiam, or an appeal to ignorance.
It is quite possible that the argument that I have put forward is not enough to convince the
empiricist of the failures of Moore’s proof. Moore’s position, “I can know things, which I
cannot prove,” is based on his argument that:
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1. Premise (1) cannot be proved.
2. Premise (1) is known.
3. Therefore, proof is not required for knowledge.
This is quite a strong argument if he can show that premise (2) is true. Moore cannot do this
without divulging into more involved proofs, which he does not do. He actually says that he
does not think that proofs of this type are possible (198). So I must question what Moore
considers knowledge. Why does he think that he knows premise (1)? He claims that he knows it
because he has no doubt that he is not dreaming and he has conclusive evidence that he is awake
(199). Is this the type of justification that Descartes had in mind? No, Moore’s evidence of
being awake is likely based on his sensory experiences, which he has failed to support with any
kind of proof. Since he cannot prove that he is awake, he must acknowledge it as a possibility,
but he considers the notion absurd.
Moore’s attempt to solve the dilemma that many other philosophers have tried to unravel
was tragically flawed from the start. He secretly uses his conclusion to back up his premise, thus
forming a circular argument. Ironically, this circular argument only takes us back to precisely
where we started. How do we know or not know that external objects exist?
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PAPER #3
Although I did not do so at first, I have come to agree with G. E. Moore’s proof of an
external world. Once I understood his view of proof, I came to agree with him based on how he
defines, explains, and defends his proofs.
Moore seems to make the case that the existence of absolute certainty is very doubtful at
best. His argument for proof of an external world is not meant to be seen as a proof of absolute
certainty. Rather, what he’s trying to show is that proof requires conclusive evidence. By
accepting that he can observe both one hand and then another he makes the claim that they both
exist based on his acceptance of the concept of their existence. He’s making an argument for
best guess based on what we know and accept. Moore points out that this is the best we are
capable of. We can not be completely certain of anything, but if we accept certain things as
truths we are then able to produce proofs within those truths.
If we are to follow Descartes’ model of knowledge as absolute certainty, then no further
proof of existence other than I am, that I exist, can be proven according to Moore. Moore is
making a leap, but not one of faith in his eyes. Faith requires believing something without proof.
Moore provides proof in his argument, but also allows that the entire argument only holds true so
long as the premises are true. To me, it sounds as if he’s saying that we must believe in
something, because the alternative would be to believe in nothing. Unlike Descartes, Moore
doesn’t look to some all powerful being, some god, to prove he exists as more than just as an
entity with no more power than a brain in a vat. He looks instead to what he is able to prove
based on experience and observation of the world in which he exists.
Knowledge based on observation is all the knowledge we possess. If indeed I do exist in
no more than a dream state that doesn’t make the truths within that dream any less true within the
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context of the dream itself. If I have the ability to fly in my dream, but do not possess the same
ability outside of the dream doesn’t make the proof that I can fly within the dream any less true.
Moore points out that he can not prove beyond a doubt that he is not dreaming. Instead, he
makes the argument that we accept that we do exist within the world we seem to exist that proofs
can be defined for that world.
Moore’s critics will point out that he can not absolutely prove the premises of his
argument, and he accepts this based on their idea of proof. Proof for them is a matter of absolute
certainty whereas for Moore it is a matter of conclusive evidence. He points out that this
conclusive evidence is the best approach we as human beings have for making an argument for
knowledge. Knowledge, in Moore’s eyes, is not a matter of certainty, but one of probability.
Knowledge is also based on what we accept as truths. To base knowledge on absolute certainty
(which Moore claims is a highly unlikely concept) would leave us with no knowledge
whatsoever as very little, if anything, can be claimed to be absolutely certain. Even Descartes’
claim that he thinks therefore he is could be questioned (though not in Descartes’ view,) and that
it could be questioned keeps it from absolute certainty. So then, the question becomes do we
accept that there are no truths at all or do we accept that there can be truths in so much as we are
able to prove them to the point at which there is little doubt as to their validity.
Although his argument can not be proven completely certain, I agree with G. E. Moore’s
proof of an external world based on his concept of what proof is as the alternative is to accept no
proofs whatsoever due to the failure of absolute certainty to exist with any proof. We can only
be so certain of anything, and must accept this limitation.
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PAPER #4
In this paper I am going to argue that G.E. Moore’s two-hand proof is a good argument
for the existence of the external world, because of Locke’s idea that the only source of genuine
knowledge is a sense of experience.
In the “Proof of an External World,” G.E. Moore argues that he can prove the existence
of the external world by simply holding up his two hands. His proof is that he can hold up his
right hand, and make certain gestures with the right hand. Then he can hold up his left hand, and
do gestures with it also. Moore can clearly say that his two hands exist, and existed in the past.
With this proof Moore could go on proving everything in the world exists, or existed at one time.
The only way this proof works is if three conditions were satisfied. First, if the premise which he
presented as a proof of the conclusion was different from the conclusion’s proof. Next, he must
know the premise which he presented, and not just believe that the premise is true. Last, the
conclusion must follow the premise that presented. The premise that he presented follows all
three of these conditions, so Moore believes that it must be true. Moore does not know of any
other conditions necessary for a rigorous proof.
I find that the following considerations that Moore and Locke provide are a convincing
argument for proof of the external world. First, Locke is a science guy that believes in probity.
Locke also says that the only way to gain knowledge of the external world is through
experiences, I find this claim plausible, for the following reason. If I touched a hot burning
stove, and burned myself, I certainly would never do it again, because of how much pain it
caused. Now you may want to know how I am going to relate this to Moore’s argument. Using
the same example of touching the stove top, I know that both of my hands are real. Then when I
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touch the stove it will obviously leave a burn my hand, so I can clearly state, here is one hand,
here is the other. I know that what I expressed in premise one is true. Therefore, I can say that
two human hands exist at this moment, and existed because of the burn on my hand. Without
experiences I don’t think it is possible to gain some knowledge. Sure you can gain knowledge
through other people, or textbooks, but some people don’t have a clear understanding until they
do it, and learn from what I did. What Moore is trying to argue is, do we really need conclusive
proof for something as simple as here is one hand, and here is the other? Is it possible to just
know that you exist and accept that everything around you exists? In some philosopher’s eyes, it
must be accepted merely on faith, but Moore disagrees. Moore thinks it is impossible to have
convincing proof of anything. Sure you can have conclusive reasoning, but you can’t ever have
conclusive evidence? In my opinion, I believe that there are something out there that you just
have to except, and something that you have to believe in, and it’s up to you to decide what you
what to believe in.
Descartes would not agree with Moore’s argument of the external world. Descartes
believes the only way to gain knowledge of the external world is to be absolute certain that it
exists. Descartes argument relies on an idea that God is an infinite and perfect being, and that
this idea was caused by something. Descartes would say that my experience is an unreliable and
inadequate means of knowledge. Descartes would just doubt the existence of me and my hand,
because he is not absolutely certain that I exist. I don’t find this claim plausible because, how
could you ever think anything is true, is it possible to be absolutely certain about anything? How
can Descartes be absolutely certain that this infinite and perfect being actually exists? Who
knows he might have got this idea of God as an infinite and perfect being from a parent, or a
friend of the family at a really young age and not remembering someone telling him about God.
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This is why I agree with G.E. Moore’s two-hand proof argument, and Locke’s idea that
the only source of genuine knowledge is a sense of experience.
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PAPER #5
I believe Moore’s assumption to be true that during that specific instance of showing his hands- they did,
in fact, exist. In this paper I will argue that G.E. Moore is quite correct in his theory of holding up one hand and
then the other proves the existence of the external world. I have faith that we are not dreaming and based on this
faith, I am absolutely certain of Moore’s premises and conclusions.
To begin, Moore offered proof of his theory by offering that he was certain that he was looking at two
hands. However, he does admit that he cannot give proof of the kind that requires some general statement or
method in which to prove his claim. He doubts absolute certainty. This doubt comes from the statement that he
cannot truly know whether he is dreaming or not. I will address this issue first.
If I were just dreaming, then I could claim to have control over every aspect of this world. If I were
dreaming, it would be possible for me to grow wings and fly, walk through walls, or any number of limitless
ideas. If I were dreaming people would just spontaneously appear and disappear because there would be no
sense in long drawn out births or deaths. We are born and die, and do not spontaneously appear or disappear. I
haven’t, as of yet, been able to grow any wings despite the wish on several occasions. I also have not (besides
within an airplane) been able to fly. I can’t walk through walls nor do I have any omnipotence or omniscience
within this world. I cannot offer any conclusive evidence or proof, but I am certain based on those previous
beliefs that I must not be dreaming. In other words, I have faith that I am conscious. The only uncertainty of this
would be that if I were not in control of my dream. To this I say that although it is somewhat believable that
we’re living in an alternate “Matrix”-like world, I have faith that we are simply here and not dreaming. I think
Moore would agree.
These conclusions lead me back to Moore and his explanation of the external world. Obviously, if you
can prove that you are not dreaming with absolute certainty, then Moore’s statement about his hands would be
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more acceptable. Moore even concedes that he doesn’t believe that he could ever have absolute certainty of
premise (1). However, the sun will inevitably rise in the East tomorrow. We could give all the evidence for
thinking this is going to happen, and yet many philosophers could say you cannot know this with absolute
certainty. This is what Moore is saying about the external world as well. Philosophers that demand proof in the
way that is described by Moore, “How any premise such as “here is one hand...” can be true” are indeed never
going to have absolute certainty for any theory of philosophy. Those types of philosophers will never gain any
knowledge because they will never accept any theory based upon the fact that you cannot be absolutely certain
of anything. This is very much like Descartes’ “brain in a vat”.
I think many philosophers could be convinced of Moore’s theory if he added an extra premise, such as
one mentioning that he has faith that he is not dreaming. Although, I believe that Moore did not include
anything like this purposely, I think Moore wanted to address the argument that you don’t necessarily need
conclusive proof to know something. He assesses (which I accept to be true as well) that one can know things
that he/she cannot prove. Is this acceptance based upon faith? Of course it is by faith. Faith is nothing more
than accepting something with certainty despite any proof or evidence. Moore knows that he cannot offer
evidence or proof that he is not dreaming, but he can accept on faith that he is not. I agree. Therefore, if we
accept on faith that we are not dreaming then we can say with absolute certainty that Moore’s argument is valid
and sound.
Now, I can see arguments that could arise from these conclusions. One might argue that (as I mentioned
before) if you are not absolutely certain of anything, and you are basing your knowledge in faith, then this
argument holds no water. I say this is not the case, and that one can even begin to conclusively accept any
argument without accepting certain premises on faith first. This is best illustrated by the example:
1. If the sun comes up in the East today, and there are no clouds in the sky, then it will be a sunny day
out.
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2. The sun came up in the East today.
3. There are no clouds in the sky.
4. Therefore, it is a sunny day out.
In this example, you had to start out this argument accepting certain premises on faith. Although these certain
premises turned out to be absolutely certain, they were still accepted as true on faith while working through the
argument. I agree that this is quite the inductive way of reasoning out arguments, but as I pointed out earlier:
just as you can be sure that the sun rises in the East, so can you be sure that you are currently real and not
dreaming. Furthermore, based on these faiths I can say with absolute certainty that:
1. Here is one hand. Here is another
2. I know that which I express in premise 1.
3. Therefore, two human hands exist at this moment.
This explanation is proof enough for Moore, and should prove to you the existence of the external world. It is
proof enough for me.