Elizabeth thinks the tree we cut down behind Harry Maskett's pond is lovely, as usual, but rather regrets taking it at all. "I think it looks better standing in the woods," she says, looking at it trimmed and aglow in the window. She's a sophomore in high school, and an environmentalist.

Sarah says her favorite course at Brown where she's a freshman, is on women in literature. She's a feminist. (Should she be called a "freshperson" or "freshwoman"?)

Steve, befoe going back to his second year of college in Boston, worries about the fate of the hostages. But he also believes the shah was, well, if not a butcher, at least a scoundrel; and he speaks critically about the legacy of American imperialism in such places as Iran. He remembers Vietnam and remains strongly antiwar.

Although I never realized it so clearly until listening to them here at "The Farm" this holiday season, all three have been shaped by the '70s. That should be obvious, I know, but sometimes home is the last place we look for lessons about the times.

My children, at least, feel themselves part of cultural movements that they believe flowered in this passing decade -- environmentalism and women's liberation most notably among them. It didn't all begin then, of course. But to think you were affected in special ways by a specific era is to give a decade of lifelike stature of its own. Who knows, someday they may even grow nostalgic about the '70s, although God only knows why.

We were sitting around the fire the other night talking about what, if anything, distinguished this artificial break in time we're about to celebrate. No consenus. Not even a trace of affection for the years of Watergate and the end of Vietnam, years of oil embargo and growing gas lines, of 14 percent inflation and 18 percent bank loans.

About the only agreement we could reach is that these recent years were characterized by a certain grimness.

The only humorist worthy of the name,. Woody Allen, flavored his portrayals of life in the '70s with a bittersweet poignancy. His people always are searching for, and always failing to find, lasting love. Woody elevated the lonely loser into an art form. The rest of what passed for humor was lifted from the past broad burlesque such as "Animal House" of the pure escapism of "Star Wars" and all its many imitators. (The true happy ending for the '70s, it seems, is to be found aboard an alien spaceship when the earthling finally leaves the problems of the old planet forever behind. As the craft lifts off, "heavenly" music sounds -- composed and played with wonderfully fitting irony, by a computer!)

One of the best social commentators of the times, Garry Trudeau, delivers his message in the panels of a comic strip. "The American dream is over, Mac," one of his characters in "Doonesbury" says. "It's been shattered into a million jagged pieces. All that's left is a nation of middle-class hustlers."

Much of the rest of what passes for entertainment is as empty, slick, and cheap as the TV fare that flits across the screen in numbing procession night after night. (One of the more hopeful signs of the decade came when it appeared that Americans had reached the saturation point, and were beginning to tune out -- and turn off -- their sets. A ripple of terror swept through the TV industry; immediately, the bad news was countered by studies and surveys designed to prove it wasn't so.)

And it says something about the times that the most incisive commentary I've seen about the '70s comes not from one of our noted writers or journals. The latest pages of a small monthly newsletter published by a New York firm -- Desner, Morris & Tortorello Research -- for corporate and political clients contain such provocative passages as:

"In politics, the fragmentation of consensus led to the single-interest politics and, even worse, further abstention from any participation in the political process. And the education of the new civilization concluded the decade by producing students whose heads seemed crammed full of more facts than had Aristotle or Bacon, but whose souls were unable to affirm any of the eternal or universal realities which have undergirded western civilization for two thousand years."

And:

"There is a paradox of power. The '70s saw America pummel a nation a fraction of our size and strength, but we couldn't win the war. We have the power to destroy the earth umpteen times over, but we are held hostage to the oil weapon. We have the power to put a man on the moon or send rockets to photograph distant planets, but we cannot yet solve the problem of global hunger which will probably be the most wrenching human concern of the '80s. We have amassed the greatest concentration of wealth, talent, knowledge, and mechanical force in the history of the human race, yet we seem unable to provide our citizens with an inner certainty that gives cohesion, common direction, or even civility to our national efforts."

The children don't think much of these ritual end-of-the decade national temperature takings. They have a healthy skepticism about what they read, particularly in the press. And Tom Wolfe nonwithstanding, they don't accept the idea that they're part of a "me generation" now closing out the "me decade." That strikes them as being terribly shallow and glib. But then they're different.

Which is about what every American father would say about his family, with about as much accuracy, as we all bid farewell to the '70s.