Of the seven deadly sins, the eighth is complacency. It is also the worst, lacking even the possibility of redemption through guilt. Anyone who tells you he worries about his complacency is not only a liar, but an (oxy)moron.

Nonetheless, one cannot repress the growing conviction that, on most of the major issues of our time, complacency is the only philosophically tenable position. Indeed, the evidence mounts in favor of a General Theory of complacency: For any putative crisis x, there is a vector of facts y such that (a) x is not happening, (b) it is not harmful, (c) it may even be helpful, (d) at any rate, it's not very important, or (e) if it is, there's nothing we can do about it.

Take, for example, the constellation of concerns surrounding the notion that Canada lacks ''competitiveness.'' Many Canadians are convinced that high spending, high taxes, high interest rates and a high C$ are driving the country to ruin.

''The root of the problem,'' the president of the Canadian Manufacturers' Association complains, ''is that Canada's public sector has not yet adjusted its spending and taxation to the new world realities.''

Really, it is all one can do to stifle a yawn. Public spending in Canada is not especially high by international standards - certainly not on social programs, the favorite whipping boy of the right. Social spending accounts for 21.5% of gross domestic product, compared to the average among developed countries of 25%. Nor are Canadians overtaxed, again using international comparisons. In 1988, Canadians paid 34% of GDP in taxes, compared to the 38.4% average for OECD countries.

There may be room for some concern on the personal side, at least for the top earners. A study by Price Waterhouse shows that Canadians earning $100,000 and up could increase their disposable incomes by 40% or more just by moving to the U.S. But it's harder for people to move than for capital and, on the corporate side, we've got nothing to complain about.

Though combined federal and provincial income taxes are slightly higher here in nominal terms, that doesn't measure the effective tax rate, once various deductions and credits are taken into account. For example, the U.S. taxes capital gains in full. It also has a 20% minimum corporate tax. And U.S. investors get no dividend credit for taxes paid at the corporate level.

Nor are income taxes the only taxes. U.S. social security levies are twice as high as those in Canada. And if it's the economic impact of taxes we're after, it's not the average tax rate that matters, but the marginal rate: what you'd pay on the next investment. Studies by the Economic Council of Canada and others reckon these to be at least as low on average in Canada as in the U.S., and perhaps lower.

Besides, there's little evidence that high tax rates, by themselves, are all that harmful. It's far more critical to keep tax rates neutral between different investments.

High tax rates may even help. When the government takes 50% of the profits, and 50% of the losses, it is in effect taking an equity position in every corporation in the country. By assuming some of the risk, it allows private entrepreneurs to take on more themselves.

High interest rates - now a third less than at their peak - are similarly overblown. Not all investment is financed by borrowing: in fact, less than 30% of it is. Moreover, while high rates may be bad news for capital-intensive businesses, they tilt the field in favor of smaller, job-creating outfits, good news for the jobless.

And high rates force businesses to be choosier in their investments, raising rates of return. Or, as one school of thought contends, it may be the other way around: interest rates may be so high because of the abundance of good investment opportunities a world market affords. Either way, real interest rates are set by global capital markets. The only rates policymakers in Canada can affect are nominal rates. And what you can't change, you shouldn't worry about.

As for the dollar, the degree to which it is ''over-valued'' - that is, above the level that would equalize its purchasing power at home and abroad - is about 5 cents, and closing. With Canadian inflation likely to undercut that of our trading partners, an unchanged nominal value of the currency would mask a real depreciation. Besides, if ''competitiveness'' means cutting costs and rationalizing production, that's exactly what the high C$ has encouraged.

The moral: If we stop worrying about these problems, they will go away. Everything is for the best in the best of all possible worlds. Don't worry, be happy. And have a nice day.