I've been trying to explain to my 9-year-old what fundamentalism is. He reads enough of the news to have learned that we are at war with a "fundamentalist Islamic regime" in Afghanistan. But he has classmates who identify themselves as fundamentalist Christians; and given the enormous diversity of life in New York, he knows children who belong to each of the world's major religions and not a few of their sub-orthodoxies. Why is fundamentalism such a bad thing, he wants to know.

What a loaded question, I think to myself as I search for words that would help him understand my distrust of virtually all fundamentalist ideologies–ubiquitous though they be–without also conveying disrespect for his friends. Perhaps there are wiser ways, but I begin by unlinking the question of fundamentalism from any one religion and try to think about a general political meaning–for after all it is with politics that the trouble usually begins.

I think that fundamentalism most frequently reveals itself in a basic relation to language, what linguists might call the notion of transparency. That is, there is very little play between the literal word and the thing to which the word refers. For a common example, if "God" refers literally to the supreme deity, the word itself is made holy, and the careless or playful use of that name constitutes blasphemy–what many call "taking the Lord's name in vain." In some traditions, writing or just saying God's name aloud is an act of hubris. Similarly, the proscription against iconography is a version of this literalism: There can be no human "play" with the representation of the divine.

This can also mean that there is not much room for creativity, figures of speech, irony, plays on words or dissent. Hence, at various moments in American history, theater and fiction were frowned upon as antithetical to religious piety and moral sobriety. As a lawyer, I think of so-called strict constructionists, who assign very literal meanings to the Constitution, who would limit its interpretation only to what the Founding Fathers actually said in 1789.

As a politically engaged citizen, I think of an objectivist friend who hews to the words of Ayn Rand with passionate absolutism. (He used to quote Karl Marx with the same unyielding fervor. The only consistent thing about him is that he still has the nerve to call me a "cultural relativist.") The eugenics of racial and biological determinism are fed by notions of blood or genes as sacrosanct. And when Mark Hunt, a former West Virginia state legislator, hired Clonaid (a company whose founders believe humans originated as clones of advanced extraterrestrials) to clone his 10-month-old son who died in 1999–well, this, too, is a form of fundamentalism, a fetishism of the body if not of words.

Religion comes from the Latin word religare, to bind back together. Fundamentalism is at root a way of insuring that one's present life forms a bridge between past and future. All faith does this, I think–links our forebears (whether founding, mythic or ancestral) to the promise of a predictable future (whether in generations to come or in an afterlife). All faiths, including the secular, probably share this basic sense of hope or longing that what we have known in the past will carry us toward a stable future. Even contract law is a way of directing present action so as to link past promises with future expectations; commercial "good faith" and trust in the market are no less ways of protecting ourselves against the chaos of the unknown.

But belief tends to become fundamentalist when it hardens into an expectation of guaranteed outcome. When the present becomes too strictly fixed as that bridge between past and future, the rigidity of ancient injunction takes over as the only true path to salvation in the world-beyond-now. This fixedness of destiny, this sense of outcome being fated, is in general tension with aspects of freedom. Divine (or constitutional) predetermination of what shall be imposes constraints on thought, channels behavior and may limit either individual or collective will. Whether this is a disciplining positive or a repressive negative depends on what is at stake, but it is always complex. The very notion of progressivism in American politics, of course, including Martin Luther King's framing of the civil rights movement, goes back to early American convictions that one's "manifest destiny" lay in carrying forward a pure (or puritanical) version of the biblical past and ferrying it in a steady line of upward progress toward the perfection of God's promised New Jerusalem.

The discussion with my son wanders broadly. Almost as an aside, he queries me about a newspaper article he's found in which the publisher of the Sacramento Bee was booed off the stage by California State University students when she raised concerns about post-9/11 limits on freedom of speech and the press. There is little new or nice, I tell him, about college students heckling speakers they don't like, but what is peculiarly inverted about this story is that the students seemed to be protesting what was essentially a defense of the very right to protest.

A sense of unremitting loss is what most often drives the fundamentalist desire to preserve ancient, pre-modern or just the last four months of history and enshrine it for the future–even if it means turning the present into a state of absolutist conformity. In that sense, fundamentalism is frequently the byproduct of an inability to accept the finality of death or other great crisis.

The angry refusal to let go of grief, in turn, can fuel blind acts of repression. We have never been a nation able to grieve easily or properly–to turn off the yammering on CNN and the yelling on Fox, disconnect the telephone, surround ourselves with friends and come to terms with the magnitude of this tragedy. But we must do something like that in order to move on unencumbered and outspoken, rather than trying to stop time by mutely uncritical allegiance to that day–that unified, yes, but horrifically frozen moment in our lives. Only then can we the people free ourselves sufficiently to tend to the exigencies of a present political order that is still very much ours to redeem.