I have to admit that initially I was uninterested, even close-minded, about the negative yield being offered on a growing share of European sovereign debt. “It must be a short-term aberration,” I thought at first. “Completely nutso,” I sniffed dismissively as the phenomenon spread. “Who in their right mind would invest in a financial instrument that would guarantee a loss of principal?” Upon calmer reflection, I would shrug and think, “Well, to each his own, but none of those topsy-turvy debt instruments for me.”

More recently, I have taken a more tolerant attitude toward negative-yield debt. As I teach my Econ 101 students, the key to success in the economic marketplace is to set aside your own preconceptions and preferences and to acknowledge that the consumer is always right. If some of my fellow human beings want investment products that repay them less than their principal, who am I to find fault?

In fact, the more I think about it, I find myself attracted to the idea of offering such a service to satisfy this unfathomable consumer appetite for negative yields. Maybe I should announce that anybody out there who would like to send me money on the condition that I return less than all of it to them in the future is free to do so (as long as they include payment for any incidental transaction costs). From that perspective, negative interest rates are quite ingenious.

Actually, (I’m going to attempt to be serious now) what really got me thinking about the growing phenomenon of negative-yield debt was how to explain the concept to my 101 students. The traditional introduction to interest rates involves three basic components. The first is the “originary” rate of interest — the time preference between the present and the future. In years of teaching economics, I’ve never yet had a student express a preference for a hundred dollars next year over the same amount today, and I doubt I would get a different response if I lowered the payoff in the future to $99.90. Conclusion: The time preference of humans doesn’t account for the increasingly common negative-yield phenomenon.

Perhaps, then, we can solve the mystery by examining the second component of interest rates — the risk factor. Students readily grasp the rationality of lenders adding a risk premium to interest rates to compensate for lending to higher-risk borrowers. Traditionally, the primary function of financial intermediation has been to assess the creditworthiness of borrowers. That isn’t always the case at present, with government citing “disparate impact” and penalizing lenders who dare to consider risk before issuing loans. I can get my head around a risk premium of zero for government debt, since central banks can use QE and other techniques to ensure that governments have unlimited ability to return to its creditors however many monetary units it has borrowed. But a negative yield? One could certainly argue that nongovernmental borrowers, not having their own central banks, can’t give 100 percent guarantees that they’ll be able to repay what they borrow, while governments do; therefore, some creditors feel safer contracting for a negative yield from a government than a positive yield from a private entity. The problem with this line of thinking, though, is that creditors could lock cash in secure storage and know that they would get all of it back, rather than paying government to borrow their money.

The third component of interest rates is the inflation premium which creditors sometimes demand to protect against currency depreciation. The late Franz Pick used to call bonds “guaranteed certificates of confiscation” because, between depreciation of the monetary unit and government taxation of interest income, bondholders’ purchasing power was systematically and ruthlessly transferred to government. Even today, in the bizarro world of central banks trying to “achieve” positive inflation (i.e., currency depreciation), one would think that creditors would insist on an inflation premium to offset the targeted depreciation. Instead, we have the spectacle of widespread acceptance of a nominally negative return on paper denominated in a currency that the relevant central bank is actively trying to depreciate.

In sum, elementary interest rate theory doesn’t solve the puzzle of why there are negative-yield instruments, so we need to look elsewhere. Perhaps the holders of negative-yield sovereign debt instruments anticipate earning capital gains due to increased demand for negative-yield securities in the future. This seems like a bet on the “greater fool theory” with central banks playing the part of the “fool.” I suppose it’s possible that in our strange new world of unlimited QE, chronic ZIRP, negative interest rates, etc., yields may become even more negative in the future, thereby rewarding those who solved earliest this counterintuitive riddle. Such a race deeper into the rabbit hole of negative yields may happen, but timid (blind?) little me won’t be on the buy side of those deals.

One other possible explanation for the phenomenon of negative interest rates is that central banks are trying to make their currency less attractive in currency exchanges. This is what makes the most sense to me — central bankers hope that negative interest rates will be an effective tool of currency manipulation in a world of competitive devaluations.

Negative interest rates are a weird and alarming symptom of profound economic dysfunction. In a healthy economy, interest rates coordinate production between the present and the future according to people’s composite time preferences. Today, those vitally important market signals are mangled, broken, shattered. Maybe negative-yield instruments will pay off in ways I don’t yet perceive, but I’m content to keep my distance from them and let others play that bizarre game. I’d rather preserve my sanity.

Dr. Mark W. Hendrickson is an adjunct faculty member, economist, and fellow for economic and social policy with The Center for Vision & Values at Grove City College.