"He Talks to Himself Sometimes..."

I had a most interesting conversation with the Doctor the day before yesterday. It started because he had been talking to himself in the kitchen, while I stood next to him, and he was saying a bunch of strange things, including asking himself if he understood. I said I didn't get what he meant, and he said, "I'm just talking to myself, that's all." leaving me thinking, That's what I didn't get. He went on mumbling for a while about how there's nothing wrong with talking to yourself, and then thoughtfully said, "Although, it is unusual to ask yourself if you understand, I suppose." He seemed to change his mind, though, since, when I laughed, he said, "If you're going to talk to yourself, it makes perfect sense to ask yourself if you understand." I didn't really know what to say, so he went off to my brother to ask him if it makes sense. All my brother said was something like "I guess so..." so the Doctor came back to me, saying, "It would be horrible to talk to yourself and then find you didn't understand." He still didn't get it when I laughed. It's very strange the way he talks to himself about things that don't make sense. I guess it falls under the old 'Ark in Space' quote: "He talks to himself sometimes because he's the only one who understands what he's saying." I certainly don't understand!