Suppose two investigators wish to determine whether divorce is harmful to children in a marriage. They gather a great deal of evidence - surveys, interviews, statistics, personal accounts, etc. - and they engage in a careful and reasoned discussion about which of the sources are credible and relevant, what their limitations are, how terms like "divorce" and "harm" should be defined, and so forth. Eventually, the investigators may reach agreement on how to evaluate the evidence. For example, they may conclude that divorce does not cause lasting harm to most children as long as the parents don't involve the children in their marital disputes or conflicts. The investigators seem to have arrived at a useful fact about the social world, therefore, and since their mutual conclusion was derived from a process of evidence-based reasoned inquiry, it can be assumed to have a certain degree of validity, objectivity and truth.
But now imagine a different outcome to the investigation. Suppose the investigators look at the same evidence but cannot agree on whether or not it indicates that the children have been "harmed." Perhaps one of the investigators interprets many of the children's responses as indicating that they have reacted to the divorce by becoming more independent and self-reliant, but the other investigator, looking at the same data, concludes that the same children are too independent and are showing a reluctance to attach to others. Further discussion reveals not only that the two investigators have different interpretations of what constitutes healthy behavior, but also that these different interpretations are rooted in different sets of assumptions about human beings, relationships, social norms, ethics, etc. Perhaps the first investigator is a strong advocate of individual autonomy and self-esteem, while the second takes a more traditionalist view of marriage, relationships, and family obligations. In the end, they "agree to disagree," and each leaves with his or her own interpretation of the data, glad to be able to associate with the social, cultural and ethical communities of his or her own choosing.
But what have we learned, in this case, about whether or not divorce is harmful? There is no definite answer. It depends on what your values are, and on the assumptions you make about human nature and the most desirable kind of society. In a sense, each investigator and each community now has the opportunity to demonstrate why it makes sense to construct knowledge about divorce in a particular way.
It appears that much social knowledge is susceptible to conflicting interpretations of this kind. In fact, studies of divorce have yielded results very much like the ones described above (e.g., Kelly,2000; Wallerstein et al., 2000; see also Wallerstein & Kelly, 1980). Does this mean, then, that there in no real answer, no "truth" about divorce? In a sense, yes; but only partly. For when investigators see things differently, they do not have to give up and agree to disagree, as in the above example. They can always discuss the issues further, consider new evidence, reexamine their assumptions, and so forth. More importantly, though, the process of reasoned inquiry always permits at least some degree of agreement. For example, there is widespread agreement that, whatever the facts about the overall harmfulness of divorce, when couples do separate or divorce they should try to avoid directly involving the children in their disputes. Such widespread agreement on fundamental points is frequently possible because, however discrepant people's assumptions and value systems may be, there are always a number of specific assumptions and specific values that are so widely shared they are essentially uncontroversial (in this case, the assumption that the well-documented emotional and behavior problems of children who have been actively drawn into marital conflict indicates harm and the belief that they should be spared such harm if possible).
Thus, the process of reasoned inquiry can usually bring people to at least some agreement about social issues. At the same time, however, even the most reasonable discussions - including those in scholarly contexts where extensive evidence is carefully considered - will still leave important questions unanswered when the underlying assumptions and values of the participants are not entirely shared. The conclusions that individual participants draw will unavoidably reflect their own particular ideals, philosophies and values; and these differences, in turn, will spawn continuing debate about social issues and the worth and advisability of specific social proposals. In the next section I will discuss some of the ramifications of these issues in more detail.