Transience necessarily affects the durational expectancies with which persons approach new situations. While they may yearn for a permanent relationship, something inside whispers to them that it is an increasingly improbable luxury.

Even young people who most passionately seek commitment, profound involvement with people and causes, recognize the power of the thrust toward transience. Listen, for example, to a young black American, a civil-rights worker, as she describes her attitude toward time and marriage:

"In the white world, marriage is always billed as 'the end' – like in a Hollywood movie. I don't go for that. I can't imagine myself promising my whole lifetime away. I might want to get married now, but how about next year? That's not disrespect for the institution [of marriage], but the deepest respect. In The [civil rights] Movement, you need to have a feeling for the temporary – of making something as good as you can, while it lasts. In conventional relationships, time is a prison."

Such attitudes will not be confined to the young, the few, or the politically active. They will whip across nations as novelty floods into the society and catch fire as the level of transience rises still higher. And along with them will come a sharp increase in the number of temporary – then serial – marriages.

The idea is summed up vividly by a Swedish magazine, Svensk Damtidning, which interviewed a number of leading Swedish sociologists, legal experts, and others about the future of man-woman relationships. It presented its findings in five photographs. They showed the same beautiful bride being carried across the threshold five times – by five different bridegrooms.

As serial marriages become more common, we shall begin to characterize people not in terms of their present marital status, but in terms of their marriage career or "trajectory." This trajectory will be formed by the decisions they make at certain vital turning points in their lives.

For most people, the first such juncture will arrive in youth, when they enter into "trial marriage." Even now the young people of the United States and Europe are engaged in a mass experiment with probationary marriage, with or without benefit of ceremony. The staidest of United States universities are beginning to wink at the practice of co-ed housekeeping among their students. Acceptance of trial marriage is even growing among certain religious philosophers. Thus we hear the German theologian Siegfried Keil of Marburg University urge what he terms "recognized premarriage." In Canada, Father Jacques Lazure has publicly proposed "probationary marriages" of three to eighteen months.

In the past, social pressures and lack of money restricted experimentation with trial marriage to a relative handful. In the future, both these limiting forces will evaporate. Trial marriage will be the first step in the serial marriage "careers" that millions will pursue.

A second critical life juncture for the people of the future will occur when the trial marriage ends. At this point, couples may choose to formalize their relationship and stay together into the next stage. Or they may terminate it and seek out new partners. In either case, they will then face several options. They may prefer to go childless. They may choose to have, adopt or "buy" one or more children. They may decide to raise these children themselves or to farm them out to professional parents. Such decisions will be made, by and large, in the early twenties – by which time many young adults will already be well into their second marriages.

A third significant turning point in the marital career will come, as it does today, when the children finally leave home. The end of parenthood proves excruciating for many, particularly women who, once the children are gone, find themselves without a raison d'être. Even today divorces result from the failure of the couple to adapt to this traumatic break in continuity.

Among the more conventional couples of tomorrow who choose to raise their own children in the time-honored fashion, this will continue to be a particularly painful time. It will, however, strike earlier. Young people today already leave home sooner than their counterparts a generation ago. They will probably depart even earlier tomorrow. Masses of youngsters will move off, whether into trial marriage or not, in their mid-teens. Thus we may anticipate that the middle and late thirties will be another important breakpoint in the marital careers of millions. Many at that juncture will enter into their third marriage. This third marriage will bring together two people for what could well turn out to be the longest uninterrupted stretch of matrimony in their lives – from, say, the late thirties until one of the partners dies. This may, in fact, turn out to be the only "real" marriage, the basis of the only truly durable marital relationship. During this time two mature people, presumably with wellmatched interests and complementary psychological needs, and with a sense of being at comparable stages of personality development, will be able to look forward to a relationship with a decent statistical probability of enduring.

Not all these marriages will survive until death, however, for the family will still face a fourth crisis point. This will come, as it does now for so many, when one or both of the partners retires from work. The abrupt change in daily routine brought about by this development places great strain on the couple. Some couples will go the path of the postretirement family, choosing this moment to begin the task of raising children. This may overcome for them the vacuum that so many couples now face after reaching the end of their occupational lives. (Today many women go to work when they finish raising children; tomorrow many will reverse that pattern, working first and childrearing next.) Other couples will overcome the crisis of retirement in other ways, fashioning both together a new set of habits, interests and activities. Still others will find the transition too difficult, and will simply sever their ties and enter the pool of "in-betweens" – the floating reserve of temporarily unmarried persons.

Of course, there will be some who, through luck, interpersonal skill and high intelligence, will find it possible to make long-lasting monogamous marriages work. Some will succeed, as they do today, in marrying for life and finding durable love and affection. But others will fail to make even sequential marriages endure for long. Thus some will try two or even three partners within, say, the final stage of marriage. Across the board, the average number of marriages per capita will rise – slowly but relentlessly.

Most people will probably move forward along this progression, engaging in one "conventional" temporary marriage after another. But with widespread familial experimentation in the society, the more daring or desperate will make side forays into less conventional arrangements as well, perhaps experimenting with communal life at some point, or going it alone with a child. The net result will be a rich variation in the types of marital trajectories that people will trace, a wider choice of life-patterns, an endless opportunity for novelty of experience. Certain patterns will be more common than others. But temporary marriage will be a standard feature, perhaps the dominant feature, of family life in the future.

A world in which marriage is temporary rather than permanent, in which family arrangements are diverse and colorful, in which homosexuals may be acceptable parents and retirees start raising children – such a world is vastly different from our own. Today all boys and girls are expected to find life-long partners. In tomorrow's world, being single will be no crime. Nor will couples be forced to remain imprisoned, as so many still are today, in marriages that have turned rancid. Divorce will be easy to arrange, so long as responsible provision is made for children. In fact, the very introduction of professional parenthood could touch off a great liberating wave of divorces by making it easier for adults to discharge their parental responsibilities without necessarily remaining in the cage of a hateful marriage. With this powerful external pressure removed, those who stay together would be those who wish to stay together, those for whom marriage is actively fulfilling – those, in short, who are in love.