At least, that's what the script calls for. But economics rarely resembles a biblical epic, and even Charlton Heston couldn't talk the dollar higher in the face of a bearish forex market. Sure, the dollar bumped up a bit yesterday, after the Minister, bowing to media pressure, pronounced himself "unhappy" with its current lowly status. But talk alone won't keep it there for long.

Nor, for that matter, will central bank intervention, as suddenly demanded by The Globe and Mail editorial board. The US$34-billion in foreign reserves the Bank of Canada keeps in its vaults, which the newspaper urges be thrown into the defence of the loonie, is enough to sustain it for about an hour and a half against a determined wave of sellers.

The only certain way to prop up the dollar is to make Canadian dollars scarcer relative to American dollars, or to supply fewer relative to the demand: That is, to tighten monetary policy. But that is to put the real economy at the service of the exchange rate; to sacrifice growth and employment, in support of a figment of the imagination.

For that is all that an exchange rate is; an opinion, on which buyers and sellers are momentarily agreed. It has no independent standing; it does not exist outside their heads.

As such there is no "right" level for the dollar. It is whatever it is: the level at which as many dollars are offered for sale as there are orders to buy.

Neither can we say, on the same reasoning, that a higher value of the dollar would be "better," or a lower value "worse." The suggestion will, I am sure, infuriate some readers, especially of this paper. The notion that the dollar is "too low" is one of those things that conservatives just know, as sure as capital gains should be exempt from tax or the problems of medicare are the fault of the federal government. In this spirit, the National Post's Peter Shawn Taylor congratulated the Minister, after a fashion, for belatedly admitting "a falling dollar is a bad thing," after many years of official neglect.

Is it? How? To be sure, a falling dollar usually translates into higher import prices, and therefore implies a lower standard of living. But, as the Prime Minister is fond of pointing out, it also widens profit margins for Canadian exporters, who are paid in American dollars, allowing them to cut their prices and expand their sales.

In any case, the dollar is simply the messenger. It is a symptom, not a cause: a warning sign, nothing more. The real problem is the complex of economic factors that conspire to make the dollar less attractive to investors. Some of these, like commodity prices, are beyond our control. Others, like declining relative productivity, would be worth worrying about in their own right. Either way, there is no reason to make a higher dollar, per se, an objective of policy.

That is, if economics is the issue, and not more intangible things like national pride.

Otherwise, it is hard to see what the fuss is about: The dire consequences that are commonly associated with a low or falling dollar do not stand up to analysis. Take the assertion, often heard of late, that the dollar's historically low rate of exchange is hastening a foreign takeover of corporate Canada, making Canadian assets available at "fire sale prices." Leave aside the question of whether this is actually happening -- net investment flows have been more south than north in recent years -- or why the Canadian owners of these assets would sell if they were getting such a bad deal. Look at it from the point of view of the prospective American buyer. You've just bought a company on the cheap, using piles of Canadian play money. Congratulations: Your purchase entitles you to all future profits earned by that company -- profits recorded in those same worthless Canadian dollars.

Or take the equally common complaint that the falling dollar has itself been a factor in lagging Canadian productivity. Rather than make the needed investments, so the argument runs, Canadian firms have simply relied on a declining exchange rate to maintain their competitiveness.

The question is: Why wouldn't they do both? If there were investments open to them that would cut costs -- and increase profits -- why wouldn't they make these, and pocket the gains from a lower dollar as a bonus? The whole argument hinges on the idea that Canadian companies are not interested in maximizing profits. If that's true, then the dollar is the least of our worries.

If we mean anything when we say the dollar is "too low," we mean it is below the rate of exchange that fundamental economic factors would suggest was appropriate in the long run. If so, it can get there on its own steam, without the help of either the Finance Minister or the Bank. If, on the other hand, the dollar is not undervalued, there would seem little point in pretending that it was, and no point at all in propping it up.