Science works by proposing and disposing of hypotheses. Hypotheses come from a lot of places: previous research results, modeling, inspiration, and plain old intuition. Our intuition is a good source of scientific hypotheses because our species has evolved to possess an implicit model of the natural world that allows us to move, eat, balance, and so forth. Of course, this model is not perfect nor is it explicit. Which is why we need science. Nevertheless, it is a good source of hypotheses, and our intuitions about where things go when we throw them are an excellent place to begin elaborating, say, a classical mechanical account of projectile motion, regardless of where in the world you are when you throw something. This is because physical laws operate uniformly on earth, modulo extremely advanced concerns in quantum physics or the philosophy of science.
Given this, it may appear reasonable to suppose that our intuition could be a good source of hypotheses regarding society and culture. After all, humans are a single species and evolved in more or less the same way, and so the intuitions we have about how we live our lives should apply to all human commuities.
In fact, however, this is not a case. There is considerable variation in the organization of human conduct. There are evolutionary reasons for this since, as you can imagine, it results in populations that are highly adaptive. ‘Culture’ is the term that anthropologists use to describe the arbitrary, conventional structures of meaning which orient conduct in human communities. The laws of physics operate uniformly across the planet, while cultural systems vary. Anthropology is the science which studies human behavioral diversity. Because culturally-influenced conduct can take radically different forms in different places, it is foolhardy to use intuitions developed in one culture as a source of hypotheses about another. For this reason, it is reckless practice for natural scientists to stray into the expert territory of our discipline simply because they believe that if they are good at testing hypotheses in one realm they must be good at it in another.
A good analogy to using the intuitions of one culture to to generate hypotheses about another culture would be to imagine a non-physicist with pre-theoretical intuitions about motion creating hypotheses about life aboard the international space station. Expectations about momentum, weight, and the behavior of fluids will founder in a micro-gravity environment. Because they have not had experience in microgravity, their intuitions will be incorrect.
Simply because you are very good at shark embryology does not mean that you are ready to speak authoritatively about human societies. And, I am sure you will agree, vice versa.
Often times specialized language in the life sciences is considered as a sign that those fields are mature and specialized, while specialized language in the human sciences is merely obfuscation or meaningless jargon. There seems to be an assumption that because biologists engage in marriage, commensality, and linguistic interaction they should, in principle, be able to understand all technical writing about these subjects. And yet somehow biologists think it obvious that layman cannot understand the the technical terminology of biochemistry, despite the fact that all laymen have metabolisms.
The analogy to microgravity is useful because demonstrates two other things.
First, our intuitions about the physical world are not completely wrong in micro-gravity. Because the space station and Los Angeles are located in the same universe, there are underlying basic similarities between both environments, and humans can adapt (because they are cultural) to both of them. Similarly, it would be wrong to argue that it is prima facie invalid to use intuitions developed in one culture to form hypotheses about another. It simply results in hypotheses which are deeply flawed, but which nonetheless have considerable appeal to people because they seem intuitively correct to them.
In fact, anthropologists spend a major part of their time dealing over and over again with hypotheses which have been definitely proven wrong — black people are ‘genetically’ good at singing, heterosexual monogamy is ‘natural’ — but which are consistently reinvented by people because these hypotheses appeal to those people’s (culturally shaped) intuitions. When anthropologists refuse to engage in discussion with laymen about these hypotheses, we are sometimes accused of being obsessed with political correctness or opposed to the ideals of scientific argumentation. In fact, the situation is somewhat different: we are acting like scientists who are too weary to engage with laymen who argue that a geocentric model of the universe is correct, and who furthermore adduce evidence to support their claims by pointing out that there is much evidence on their side. For instance, sources from the Internet (often from thirteenth century Europe) arguing for a geocentric view of the universe as well as the obvious fact that the sun sets regularly while the earth does not move.
Just as it takes a special sort of biologist to spend all of his time explaining evolution to creationists, so too does it take a special sort of anthropologist to give up their research and teaching and spend precious time explaining to the public sphere why their intuitions are wrong. It is a sign of progress that we consider some questions settled, at least until disconfirming data — not mere intuitive dissatisfaction with our findings — is made evident.
Second, just as the space station and Los Angeles occupy the same physical universe, so too do human communities share an underlying biological constitution. Just as our intuitions about the physical world can be improved through examination of many different physical environments (I imagine this would include microgravity, nanoscale, and low-temperature environments) so too can our intuitions regarding social life be improved by learning about places with different cultural orders. In making this argument about our intuitions I am not arguing that science is impossible or that people from other cultures are fundamentally inscrutable.
Indeed, it is to the credit of physicists that they have been able to develop models of the world that are sufficiently general that they can explain the dynamics of movement in both microgravity and normal Earth gravity. Indeed, Microgravity is a compelling experimental environment precisely because it allows us to increase the power of scientific models in a wide variety of scientific disciplines. Anthropology, similarly, requires cross-cultural research to develop theoretically. And this is the goal of (many) anthropologists.
Expertise in one academic discipline does not automatically translate to competence in another academic discipline. It is not the case that one discipline’s present is somehow destined to be another’s future. Different disciplines develop in different ways theoretically and methodologically, because of the nature of the object they study and the questions they are asking.