People ask where my ideas come from. I am never sure. But this one I can track directly. I had lunch one day this week with a woman who told me that she likes to ride horses, and so, from time to time, she rents one. At the time she said it, the comment struck me as faintly odd, but I could not immediately say why.

The following morning, absurdly early - half-an-hour ago, as I write this - awakened by a bizarre nightmare about hats in the Deep South, I simply had to find and listen to a Randy Newman song, one of his earliest, called "You and Me". I did not know why I had to play it, but sure enough, when I found it, there was the lyric my mind had been searching for.

The song is about a fellow who's in love, singing to the woman he wants to marry. "We'll have a kid," Newman sings, "or maybe we'll rent one. He's got to be straight; we don't want a bent one."

The concept of renting preceded the introduction of money, indeed brought about the need for cash. Although no one knows for sure exactly when it was, it seems likely to have been in Sumeria about 8,000 years ago. Humanity had passed though the hunter-gatherer stage to become farmers; each man had his own plot of land and, in time, a barn or some such structure, in which to store excess crops, horse feed and so on.

And it came to pass that two men, whose names we will never know, hit upon an arrangement. Let's call them Ig and Stig. Ig was producing more crops than he could store; Stig had a spare barn. Stig rented his barn to Ig. This story may be apocryphal for all we know, but I rather like it. Money was invented at around this time, we do know that. The story is as good as any other for explaining why.

Ig had to pay Stig and, presumably, did so at first by giving Stig some of his extra crops. That would have rather neatly averaged things down. But in time, a medium of exchange less complex and perishable than crops would have been needed, and someone came up with idea of dough (a slang term for money that suggests that its progenitor might have been baked goods, except that I made that up. Money puts food on the table, hence its nickname as dough).

Of the items that we rent, homes are surely the largest. It is possible to rent just about anything for the time you need it, including, it seems, a horse. What struck me as odd about renting a horse is that, in reality, no one can own a horse. Horses are symbols of all that is free and unfettered. I have seen wild horses, in Nevada, and I am telling you, no one can rent a horse.

My friend said she does, and I have no reason to believe she was lying, particularly since I found out that she is some kinda genius. Renting is the ideal way for the owner of something not immediately needed to lend it to someone else and to derive a suitable recompense from the bargain.

I rent a home, but that too has always struck me as faintly ludicrous. If I had a lease of a decent length, it would be a nice home, because I would fix it up. I would make it "mine". Instead, it's month-to-month, not because my landlady might ever need to live in it - I do not know her, but I am sure she would rather die than the live the way her tenants do - but because economic conditions change, and one day she might need to knock it down in a great hurry. That day looms right now, as a matter of fact, so although I have lived there for eight years, the month-to-month rental agreement was a shrewd move on her part.

Conversely, I have a 999-year lease on my London apartment. I cannot be certain, but I doubt I will see the lease through. If I do, I would be entitled, under current law, to another 999-year lease. I would be older than Mel Brooks's 2000-year-old man if I should need another renewal.

And if that all sounds ridiculous, consider this: I have a friend in London who rents women. I do not know the details, but I imagine he rents them by the night (He is a buyer, rather than a seller). I am utterly opposed to prostitution, which I consider a temporary form of slavery, but at a Generation X gathering a few weeks ago, I raised the subject, only to be roundly denounced by several of the women present, who said they saw no harm in prostitution. (I will not go into it at length here, but when I promptly offered one particularly good-looking young woman who said she had no objection to prostitution $100 for a quickie, she was quite offended).

I digress. I have been trying to convince myself, as I type away, that you can indeed rent a horse, but frankly, I cannot do it. The horse "belongs" to someone else, and the easiest way to explain that reality is to say that its "owner" pays the bills for it. That much I understand. But that makes the horse a liability, rather than an asset.

Once, in West Virginia, I was staying on a farm with some friends. A horse wandered onto their property. It was a friendly animal, which is another odd thing to say, if you think about it, because horses do not speak.

I should say it had a friendly manner.

Anyway, my pals were for calling the police to report that they had found a horse. This particular bit of West Virginia was all green fields, pretty much what I imagine horse country must be. Why not keep the horse, I asked. It obviously liked being there. And the thing with a horse, especially on a farm, is that you never know when one might come in handy. Maybe the woman next door would like to rent one, from time to time.

My friends were appalled and called me a horse thief, which reminded me of the time someone accused me of stealing his girlfriend. Nonsense; you cannot steal women. Like horses, they bite.

Karl Marx, it is wrongly said, described property as theft (Engels actually said it, or maybe it was Derrick Burgess). You cannot, for example, own beer; you rent it. Not long after you have "bought" it, it is gone.

Now, as the sun comes up, I have decided that I was right all along: you cannot rent a horse. You can rent a painting of a horse; you can put your money on a horse; you can borrow a horse and make a contribution to its upkeep; you can steal a horse; but you cannot rent one.

Next time I see the young woman in question, I will have to explain this to her. It will be good for her education. She already has an education, of course. She bought it; or, more precisely, if you accept that her teachers merely opened her eyes to the information and then kept it, you might say that she rented it.