What do you think of "historical forgetting"? Not in the popular sense, but among fellow academics in your subfield? Are the same ideas rediscovered every few decades? Is history a cumulative venture? Are there paradigm shifts or trends within the discipline?

These are all things I've been thinking about in terms of my own home discipline, sociology. I was recently reading an article called "Sociological Amnesia" (ungated PDF). Here's the opening few paragraphs:

When I was a graduate sociology student many years ago, I visualized "the literature" as an ever-growing mountain of sociological findings that would continue to grow until, someday, the discipline had obtained reasonably complete and perfect knowledge about the workings of society.

Others held more sensible versions of this image, but the hope that scientific research could be cumulative -or mountain-building -was forever destroyed by Thomas Kuhn's finding (1962) that the paradigmatic axioms that underlie everyday "normal science" are overthrown and replaced periodically. However, Kuhn did not go far enough. Even the normal science that is conducted while paradigms remain dominant is not cumulative, at least in sociology, for empirical researchers regularly carry out research that repeats findings already reported by earlier sociologists.

Moreover, they do so not to replicate previous findings. Indeed, they often do not know the earlier work, thus redoing what does not need redoing instead of moving ahead to new knowledge. No wonder the discipline is often accused of reporting common sense, i.e., the already known, or not contributing enough to the stock of social knowledge. Only social theory seems to be exempt from this rule, for theoretical writings often build on the ideas of past major theorists.

The hypothesis that normal sociological science is not cumulative is hardly new. Pitirim Sorokin made it the lead theme of his 1956 book Fads and Foibles in Modem Sociology and Related Sciences , and I would imagine that someday archaeologists will dig up a Babylonian tablet making the same point.^2 (Sorokin, 1956:3-4)

Today, as surely in the past as well, the amnesia hypothesis is regularly discussed, often in personal terms, whenever older sociologists meet, and tell each other that young colleagues are reporting findings they had reported in the past. Professional pride, and perhaps also the fear that they would be stigmatized for their age, has discouraged older sociologists from publicly voicing their dissatisfaction. However, anyone who began to do research in the 1950s and 1960s must by now have seen repetitions of their own findings, almost always uncredited. I have found it happening in the fields in which I have worked, among them the sociology of housing, the suburban community, poverty research, and the media. A colleague who did not know I was working on this paper wrote recently, "I know that this is a damaging sign of advanced age, but I am struck continually that so many 'new' policy ideas are refrains of the 1960s."

The best part is footnote 2:

Robert K. Merton alerted me to Sorokin's book, and to the fact that his first chapter is entitled "Amnesia and New Columbuses." I do not know whether my use of the same title is a matter of independent discovery or unconscious borrowing of another author's work, however.

Merton had found reason to question the cumulative nature of research in his early work in the natural sciences, but he expressed the situation in the social sciences dramatically at the end of On the Shoulders of Giants, quoting David Zeman to the effect that "in the social sciences, each generation steps in the face of its predecessors." (Merton, 1965:267, 267n).

Even he didn't know his argument was a repetition of an earlier argument until he was already writing it!

His argument boils down to this:

• Sociology is surprisingly not very cumulative. That is, literature often doesn't build on old literature towards new, fuller views of what happened

• Very often, "new" findings (especially small findings) are repetitions of things from 20 or more years ago that the new young sociologist simply hasn't read.

• This is in large part, he argues, because of how reading works. The findings are repeated because the old stuff (besides capital-t Theory) simply isn't read that much. You can measure this from citations: in most sociology books, more than 50% of the citations are from the decade before publication. Another quarter are from the decade before that. Less than 1/5 of the citations are more than 20 years old!

• In theory, the insights of the past should come down through the literature. Isaacson comes ten years after Avram and Sarai and cites them both, Jacobs comes ten years after Isaacson and cites him and has presumably read people like Sarai and Avram, hopefully someone working the subfield will be able to get their core insights because they've been incorporated into Isaacson and Jacobs. Of course, that's not the way it actually works--instead, Yusuf comes along and accidentally rediscovers the ideas of Sarai and Avram but presents it as a new idea, a critique of the position of say Jacobs--even though Jacobs already knew and dealt with that idea when it was Avram's.

This happens all the time in sociology. In fact, my dissertation relies on that. It's about Turkish politics and basically says, "Look, all the ideas that anthropologists knew in the 1960's and 1970's are true, and they've simply been forgotten. If we put their findings in conversation with subsequent work by anthropologists, sociologists, and political scientists, we'll get a very different picture of how things have changed or stayed the same." By knowing the literature from a generation or two ago, I have an advantage over my colleagues. But no one expects me to know this literature and even the people of the generation before me aren't really citing it anymore (I'm looking at maybe 10 old ethnographies and the median one has probably only been cited two or three times in the last twenty years). A lot of dissertation isn't discovering new knowledge; it's rediscovering old knowledge.

This is very common in sociology right now, there are a lot of arguments about it, how we should be more cumulative or how we should better remember the past. Publish or perish is pushing the publishing of marginal pieces, piddling additions to the literature that are likely to just repeat older piddling additions.

Does the same thing happen in history? I get the sense it's less likely, and you're expected to read much older pieces than I am. There are a few classics from the 1980's I am supposed to read, a couple pieces of "classic" theory, but for the most part, older stuff gets forgotten. My dad is a sociologist as well and he's helped out a few of my friends working in random subfields simply because he remembers reading a piece or two on it (taxi cabs as a job, etc) that were published while he was in graduate school. Ideally, resources like google scholar should help alleviate things stuff, but I don't think they do.

I am very curious about how you think of cumulative ideas. I know some people have read a lot of tremendously old stuff in your subfields, but I don't know how general that is in some of the more popular subfields. You historians, do you stand on the shoulders of giants, or do you step on the faces of your predecessors?