G. E. Moore’s “Proof of an External World”

Earth Seen from Apollo

Does the external world exist? Most people don’t really question this. But how could you prove it? Since Descartes’ arguments in his Meditations, philosophers have discussed whether the existence of the external world can be proven. In this post, I want to summarize G. E. Moore’s famous talk, “Proof of an External World.”

G. E. Moore begins the paper by saying that, even though Kant claimed that there could be only one possible proof of the external world (the one Kant gave), to Moore it seems that many perfectly rigorous arguments can be given. Suppose he holds up his right hand and says, “Here is one hand”; and then he holds up his other hand and says, “Here is another hand.” To Moore, this is a perfectly rigorous proof of the proposition “There now exists two hands.”

Here is Moore’s argument:

  1. Here is a hand.
  2. Here is another hand.
  3. Therefore, there now exists two hands.

(3) implies that an external world exists, so the argument proves the existence of the external world.

Three things are necessary for a proof to be considered rigorous:

  1. The premises must be known.
  2. The conclusion must be different than the premise(s).
  3. If the premises are true, then the conclusion must be true.

Moore says that these arguments are met in the “Here is a hand argument,” because:

  1. (The First Requirement) When he is holding up one hand and then another, he certainly he knows that “here is one hand” and “here is another.” He knows this as well as he knows that he is standing there. Surely there is nothing more certain than that he is holding up his hands.
  2. (The Second Requirement) Although he recognizes that there might be some people who would think the conclusion “There exists a hand” to be no different than the premise “Here is a hand,” Moore argues that the conclusion is different from the premise because the conclusion could be true even if the premise is false. (If he had his hands amputated, “Here is a hand” would be false, but “There exists a hand” would be true in our world. In fact, many hands exist.) So, the premise and the conclusion are not identical, since one can be true and the other false.
  3. (Third Requirement) If the premise “Here is a hand” is true, then surely the conclusion “A hand exists” is true.

Moore says that, if this argument is perfectly rigorous, as he thinks it is, then it should be obvious that many more can be given.

He says that his argument would be accepted as a good argument in normal, everyday circumstances. If someone were to question whether there were three typos on a certain page in a book, it would be a perfectly acceptable proof to open the book and say “Here’s one typo, here’s another, and here’s the third.” That’s be acceptable proof.

Besides the question of whether the external world exists now, philosophers are interested in whether it existed in the past as well. But, Moore claims, proofs similar to the one above would show the past existence of an external world. The proofs will resemble the proofs of things existing now, but they will also have important differences. One such proof could be: You remember that a few minutes ago I held up one hand, and then the other, therefore, two hands existed in the past.

Moore knows that his proofs won’t convince many philosophers. They want something more than this, but it can be difficult to know exactly what else they want. One thing they probably desire is a proof of the premises of Moore’s argument. But, Moore says, he won’t give one, nor does he think one can be given. To prove that Moore really held up his hands would require, as Descartes pointed out, that Moore prove he isn’t dreaming. Moore doesn’t think he can do that. But he can know that he is holding up his hands, without being able to prove it. That’s all he needs. (So, Moore claims that I know x doesn’t imply I can give a proof of x.)

They also would object to Moore’s proof since some philosophers think that his proof isn’t conclusive if he can’t prove his premises (so either they think that a rigorous proof requires that the premises be proven or, at least, provable; or they think that to know something means that you can prove it). Moore, however, rejects this idea, even though it is common among philosophers. People claim that if you can’t prove something, you can only accept it on faith. But Moore says this isn’t so. You can know something you can’t prove. So, their objection is misguided.

Stephen Hawking on the Possibility of Heaven

Stephen HawkingIn 2011, CNN.com published, “Heaven is ‘a fairy story,’ scientist Stephen Hawking says.” The article is brief, and so it does not offer any sustained argument by Hawking against the possibility of an afterlife. In fact, I only found one section that contained anything like an argument against the possibility of the afterlife:

“I regard the brain as a computer which will stop working when its components fail,” the physicist said in an interview published Sunday in Britain’s Guardian newspaper. “There is no heaven or afterlife for broken down computers; that is a fairy story for people afraid of the dark.”

I’ve frequently heard this type of argument. I first remember encountering it in Bertrand Russell’s Why I Am Not a Christian. I read this book during my first year of college, before I had read any serious works of philosophy of religion. Even then, though, I found it to be an unconvincing argument.

His explanation for why our life cannot be revived after death refers only to natural processes. The brain is like a computer, so when its parts fail, it will stop working. A computer that has been smashed into a million bits no longer operates; a brain that has decomposed into a million bits of matter likewise cannot operate. The natural processes does not allow for that.

But this argument doesn’t come close to harming the traditional reasons for the afterlife. The traditional belief in the afterlife is based on the existence of a God powerful enough to restore and revive our bodies. God created the world from nothing. A God that powerful can restore my brain even after it has been decomposed. Any “information” lost in the decomposition could be restored. Hawking gives an argument from natural processes to show why the afterlife is not possible, but the traditional reasons are all based upon the supernatural process of God restoring the person’s life.

Hawking’s argument against the afterlife is as compelling as the argument of someone who, upon hearing me say that I will glue my broken coffee cup back together so it can hold coffee again, tells me that it cannot hold coffee because it is currently in three pieces. But I never claimed that my coffee cup would hold coffee in its broken state. I only said it could after it’d been restored.

Likewise, Christians do not claim that the brain will work in its decomposed state, but that it will work after it has been restored.

Hawking’s argument against the possibility of the afterlife is bad and unconvincing. It reflects poorly upon the church that we allow so many Christians to be fooled by such bad arguments.

John Wesley’s Prayer Life

John Wesley Prayer RoomIn Martyn Lloyd-Jones’ Preaching and Preachers, Lloyd-Jones discusses the essential need for each minister to pray often. He used John Wesley as an example. He said:

John Wesley used to say that he thought very little of a man who did not pray four hours every day.

Wow! Wesley would not think much of me. I did a little search to see what else I could find about John Wesley’s prayer life and thoughts on having regular prayer time. Here’s he best description I found.

At Arminian Today, The Seeking Disciple wrote:

John Wesley would rise up at 4 AM every day to seek God for the first four hours of the day.  In his later years Wesley was known to spend up to 8 hours in prayer.

The Seeking Disciple also had a picture of Wesley’s prayer room, which I have included in this post.

In today’s church climate, where ministers devoted to the Word and prayer are valued less than ministers who can design the best ministry systems and run the staff effectively, it is difficult for a young minister to see John Wesley as a model for ministry.

But shallow ministers create shallow churches. Our weak churches need ministers who seek God in prayer and study for hours each day. Let’s pray that God raises up ministers who make seeking God the core of their daily work. (And pray that God makes me into that type of minister.)