People can convince themselves to believe anything, or so it would seem, as the financial meltdown continues to unfold and, unfortunately, expand.

Isn’t it amazing how clear it becomes once something collapses that it was all just another version of that oldest of architectural tricks–the house of cards. But while it was happening, there are usually only a very few isolated voices trying to pierce the din with warnings and other cautionary reminders.

People, it seems, just love getting caught up in a mania. Let’s fly with emotion, and reason be damned.

It doesn’t matter whether that mania is for stocks of start-up technology companies whose horizon for any kind of meaningful profit is somewhere over the rainbow; or for real estate investments that supposedly can be flipped for huge profits ad infinitum; or, going back in history and across the ocean, for tulip bulbs.

And let’s face it, it’s not just individuals that get caught up in the madness. It’s whole swaths of the population, not to mention whole segments of the business world. And it’s this factor that makes the situation so interesting. After all, how much would anybody really care about only one lemming diving off a cliff?

No, it’s the fact of their collective madness that has made lemmings a reference point for human conduct.

All of this brings to mind some of the lessons we really should be teaching our kids in school (and at home) but which seem to be getting short shrift in our educational factories.

First lesson: If something seems to be too good to be true, it is.

The sage graybeards among you will pooh-pooh, saying “that’s only common sense.” To which my reply would be “it ain’t that common.”

The whole point, after all, about these manias that grab us is that the up-and-down cycle so intrinsic to life has been banished: tech stock prices can only go up; housing prices can only keep rising; someone somewhere will give me more for my tulip bulb than I paid for it.

Second lesson: Debt bites. And once it sinks its teeth in, it’s hard to pull them out. Tennessee Ernie Ford sang it best some 50 years ago in a song called “Sixteen Tons,” whose refrain started with the words, “Sixteen tons and what do you get? Another day older and deeper in debt.”

Just think of the expressions we use to characterize debt: monkey on your back, ball and chain. Yet these images seem to be powerless in helping many people resist the siren song of buying what they can’t afford simply because they want it and won’t wait until they have the wherewithal to get it.

We need to start constantly reinforcing with our kids (and ourselves as a society, obviously) what Mr. Micawber finally learned in “David Copperfield”: “Annual income twenty pounds, annual expenditure nineteen nineteen six, result happiness. Annual income twenty pounds, annual expenditure twenty pounds ought and six, result misery.”

(For the sake of our kids, though, let’s translate that into American currency.)

Third, while you may think that rainy days will never come, save for them anyway. “Let a smile be your umbrella” was a big hit many years back, but I think experience has shown there’s nothing so rainproof as having money in the bank.

Going back to lemmings, most accounts or pictures show them at the moment of diving, as if that were the end of it. But taking the process to its natural end, it becomes clear that lemmings are not the (real) animal world equivalent of Wily Coyote who “pick themselves up, dust themselves off and start all over again.”

They pay a stiff price for their madness–and so do we, it seems, over and over and over.