Trilemma of Lucy

In "The Lion, The Witch and the Wardrobe", Peter and Susan inquire of Professor Digory Kirke about their sister Lucy and whether she might be mad for suggesting a world exists within the wardrobe.
Digory proceeds to give the children a lesson a logic which seems to be an allegory for C.S. Lewis' famous "trilemma", given in his book Mere Christianity. In the trilemma, Lewis' argues that the claims of Jesus Christ to be the personal embodiment of the one true God give us only three options for response.

We must say he is either 1) a lunatic, 2) a liar or 3) lord and God. We must never say, according to Lewis, that Jesus Christ was merely a great moral teacher like Sidhartha Gautama (Buddha), Ghandi or Confucious, for no one can be a great moral teacher and yet constantly make false claims of being the supreme deity in authority over all he encounters and surveys.

So we must either say that Jesus was a pathological liar, despite being highly regarded as a moral teacher. Otherwise we must say that this man was in fact quite mad, despite many regarding him among the wisest, wittiest men who ever lived.
Or if we reject these, we are forced by reason to affirm that Jesus Christ is God incarnate and holds a personal claim over our very lives.
You may listen to my narration while following in the text below

mp3 file of Professor's Logic

...the Professor said "Come in," and got up and found chairs for them and said he was quite at their disposal. Then he sat listening to them with the tips of his fingers pressed together and never interrupting, till they had finished the whole story. After that he said nothing for quite a long time. Then he cleared his throat and said the last thing either of them expected:
"How do you know," he asked, "that your sister's story is not true?"
"Oh, but -" began Susan, and then stopped. Anyone could see from the old man's face that he was perfectly serious. Then Susan pulled herself together and said, "But Edmund said they had only been pretending."
"That is a point," said the Professor, "which certainly deserves consideration; very careful consideration. For instance - if you will excuse me for asking the question - does your experience lead you to regard your brother or your sister as the more reliable? I mean, which is the more truthful?"
"That's just the funny thing about it, sir," said Peter. "Up till now, I'd have said Lucy every time."
"And what do you think, my dear?" said the Professor, turning to Susan.
"Well," said Susan, "in general, I'd say the same as Peter, but this couldn't be true - all this about the wood and the Faun."
"That is more than I know," said the Professor, "and a charge of lying against someone whom you have always found truthful is a very serious thing; a very serious thing indeed."
"We were afraid it mightn't even be lying," said Susan; "we thought there might be something wrong with Lucy."
"Madness, you mean?" said the Professor quite coolly. "Oh, you can make your minds easy about that. One has only to look at her and talk to her to see that she is not mad."
"But then," said Susan, and stopped. She had never dreamed that a grown-up would talk like the Professor and didn't know what to think.
"Logic!" said the Professor half to himself. "Why don't they teach logic at these schools? There are only three possibilities. Either your sister is telling lies, or she is mad, or she is telling the truth.
You know she doesn't tell lies and it is obvious that she is not mad For the moment then and unless any further evidence turns up, we must assume that she is telling the truth."
Susan looked at him very hard and was quite sure from the expression on his face that he was not making fun of them.
"But how could it be true, sir?" said Peter.
"Why do you say that?" asked the Professor.
"Well, for one thing," said Peter, "if it was true why doesn't everyone find this country every time they go to the wardrobe? I mean, there was nothing there when we looked; even Lucy didn't pretend the was."
"What has that to do with it?" said the Professor.
"Well, sir, if things are real, they're there all the time."
"Are they?" said the Professor; and Peter didn't know quite what to say.
"But there was no time," said Susan. "Lucy had no time to have gone anywhere, even if there was such a place. She came running after us the very moment we were out of the room. It was less than minute, and she pretended to have been away for hours."
"That is the very thing that makes her story so likely to be true," said the Professor. "If there really is a door in this house that leads to some other world (and I should warn you that this is a very strange house, and even I know very little about it) - if, I say, she had got into another world, I should not be at a surprised to find that the other world had a separate time of its own; so that however long you stay there it would never take up any of our time. On the other hand, I don't think many girls of her age would invent that idea for themselves. If she had been pretending, she would have hidden for a reasonable time before coming out and telling her story."
"But do you really mean, sir," said Peter, "that there could be other worlds - all over the place, just round the corner - like that?"
"Nothing is more probable," said the Professor, taking off his spectacles and beginning to polish them, while he muttered to himself, "I wonder what they do teach them at these schools."
"But what are we to do?" said Susan. She felt that the conversation was beginning to get off the point.
"My dear young lady," said the Professor, suddenly looking up with a very sharp expression at both of them, "there is one plan which no one has yet suggested and which is well worth trying."
"What's that?" said Susan.
"We might all try minding our own business," said he. And that was the end of that conversation.

text taken from

~ C.S. Lewis, The Lion, the Witch, and the Wardrobe