Canada strives to answer question 'what is Canada?'

''A Canadian is someone who knows he is going somewhere but isn't sure where.'' Those words are probably as valid today as they were 20 years ago when Canadian historian W.L. Morton used them to answer this reporter's questions about Canada and Canadians.

Yet Canadians today are a lot closer to knowing where they are going than they were then. Canada in the past generation has made giant strides in finding its way and in settling its accounts with history.

And if Canada continues to have something of an identity crisis - and it does - that crisis appears closer to resolution. One reason may be Prime Minister Pierre Trudeau's action of ''bringing the Constitution home'' in 1982.

That step transferred authority for the British North America Act of 1867, under which Canada is ultimately governed, from London to Ottawa.

For a nation that has enjoyed independence for more than a century, there was something of an anomaly in having that ultimate authority, even if it never really was exercised, residing 3,000 miles across the Atlantic rather than right at home. Yet Canadians for decades in this century seemed untroubled by the arrangement.

Even now, opinion polls suggest that a great many Canadians themselves do not fully understand just what this transfer of constitutional authority really implies. To many Canadians, the transfer is more symbolic than actual.

What is taking place in Canada today is a subtle but vital realignment of Canadian government, its social contract, and the way in which Canadians relate to their government and their society.

''This is a time of change and awakening, but it is so subtle that we are really not aware of all that is going on or its implications for our future,'' said one member of Trudeau's Cabinet.

Canadians are often hard put to find differences between themselves and their cousins south of the border in the United States. After all, excluding Quebec and the French-speaking minority here, the language, the culture and life style, and so much else are similar at first glance.

But there are real differences. The very fabric of society is part of the difference. Coming 90 years after the US Declaration of Independence, which called ''life, liberty, and the pursuit of happiness'' the inalienable rights of US citizens, the British North America Act of 1867 spoke instead of the rights to ''peace, order, and good government'' as essential to Canadian existence.

In Canada, as social historian Pierre Berton says, this means that good government is strong government - a vital difference between the social compacts of the two neighbors.

Canadians accept a much stronger government, and more governmental intervention in their lives than would be the case in the US. This could change, but for the moment the tradition of the government keeping a regulatory hand on much of the nation's progress is very strong in Canada.

It should not be overlooked that while the western US was settled by an aggressive, hardy lot of pioneers striking out largely on their own, Canada's west was ''led and controlled by the Northwest Mounted Police,'' as historian Morton put it. These disciplined men brought law and order to the Canadian westward movement before it even began - and the ''Mounties'' (now the Royal Canadian Mounted Police) continue to play that role in the vast, untapped and undeveloped frontier regions of Canada's north.

Canadians have double loyalties. Other nations do, too. But in Canada there is a difference. There is a deep attachment on the part of most people to provincial and regional areas that often is more important than the nation itself. Yet this regionalism plays against Canada's huge physical size (3.85 million square miles).

''These regions are so widely separated from each other, so dramatically different, that it is sometimes hard to envisage Canada as a whole, in all its varied vastness,'' says former Canadian ambassador to Washington, Charles A.E. Ritchie, adding:

''In the case of Quebec, all such differences are of course immensely accentuated. French-Canadian society has held on to its own values and its own language for eight generations. No attempt at cultural assimilation has succeeded in the past, or is likely to succeed in the future.''

The debate over political arrangements goes on, however, touching on the deeper issue of the type of nation Canada wants to be.

The Canadian nation, once seen as hopelessly split between Anglophone and Francophone peoples and cultures, is bound to remain bilingual and bicultural, but it now appears unlikely to unravel over this issue despite persistent separatist trends in Quebec.

Canada, of course, could ultimately split apart over this situation, but the shapers of Canadian life suggest that rather than coming apart, Canada will find a satisfactory accommodation to the uniqueness and growing vitality of the French culture in Quebec.

Only several years ago, few people would have been so hopeful.

Maybe the reason is that Canadians have better come to terms with the idea of Canada as a ''mosaic'' of peoples rather than as a ''melting pot'' of peoples. Many ethnic flowers can, therefore, bloom within the whole.

Still, the final dimensions of what Canada is to become are unclear. In part this centers more on geography than culture. Canada is essentially what the longtime Prime Minister W.L. Mackenzie King once called ''a nation of regions.'' And it is likely to remain so.

In a Canadian identity crisis 15 years ago, Maclean's magazine gave Canadians three options for a redrawing of the map of Canada.

The first consolidated the present provinces and territories into eight subdivisions including two ''city provinces,'' embracing what are now Montreal and Toronto, calling the latter York. French-speaking Quebec was a separate entity, as was industrial Ontario and Atlantic Newfoundland. The Maritime provinces, the midwestern and western prairie provinces, and far-west provinces were grouped together into three unique entities.

The second option was an independent Quebec with the rest of Canada divided between Canada East and Canada West, a bit like Pakistan when it was first formed. French separatism was building to a new crescendo at the time.

And a third option merged Canada into the US, leaving Quebec as a Puerto Rico-like free state attached in semi-permanent fashion to the US. There were many Canadians at the time who saw little likelihood that an independent Canada could survive nestled up against the most powerful superpower in the world.

That the two final options have more or less been nudged aside in the 15 years since Maclean's published its proposals suggests just how far Canada and Canadians have come in less than a generation.

Many a Canadian now agrees with Newfoundland novelist Harold Horwood who in a bit of premature hyperbole suggested a generation ago that among western nations , ''Canada is the first truly 20th-century nation.''

That may stretch the point a bit, but Canada truly is a vigorous and important 20th century land, one that plays a significant international role as an independent voice in world councils.

As Canada moves into the final years of the 20th century, it is likely to make further refinements in the way it governs the vast reaches of its 3.9 million square miles.

Perhaps most important for Canadians is the fact that they now recognize that ultimately they, and only they, are responsible for their own future. ''Bringing the Constitution home,'' as Prime Minister Trudeau's government did a year ago, was a step that has finally given Canadians responsibility for their own destiny.

Previous articles in this series ran July 12, 13, 14, 15, and 18.