In the neverending battle to define "what is real" for each other, to persuade each other of what is good, bad, and important, one disturbing trend in academia is to jump on the bandwagon of things considered "socially constructed." The banner of social construction has become a lightning rod of sorts for all sorts of bizarre things that represent what the author refers to in terms of "rage against reason." X was socially constructed, and therefore is unreal, and even bad, and should be modified or replaced by Y.
Emotions, knowledge, the mind, the economy, the deficit, gender, mental illness, even facts and reality, all have been subjected to literary claims that they are "socially constructed."
Hacking provides an interesting perspective on this whole trend by de-emphasizing the social aspect and focusing on the construction aspect. He views this simply as a way of arguing against the inevitability of something. For example, arguing about 'social construction' of our understanding of quarks in physics, part of the standard model, the question becomes whether an alternate equally successful science could have arisen that had no such concept as a quark. Hacking then struggles with what a successful science means, and how we would recognize it. There are many examples that follow this pattern, each discussed in terms of whether X was inevitable, and thus how else it could have been constructed in our minds and in culture.
Hacking goes as far as an offhanded treatment of nominalism and essentialism relevant to this inevitability question (essential qualities are those that are seen as inevitable). He breaks down difficult questions into relatively simple ones using this same kind of straightforward procedure. In analyzing the social construction of X for many examples, he looks for those elements of X that were inevitable, and those that serve "extra-theoretical" purposes and could have been constructed differently.
One particularly unique aspect of hacking's work here, the prototype of social constructionism here is not the sociology of science in general. He uses Pickering, LaTour, and Woolgar as his prime examples, rather than folks like Harry Collins and Trevor Pinch, who are often considered in the same category. Hacking considers them distinct for his purposes, and this reveals some interesting distinctions.
What I liked best about this book is that while it is carefully done, there is an offhanded air about the points Hacking makes. He makes some very difficult analyses seem very easy by pulling particularly useful examples from the literature. He navigates a lot of difficult philosophy by asking deceptively simple questions, like "what is the point ?" rather than "what is the meaning ?"
There are some interesting sweeping gestures here like claiming that social construction can simply by thought of as an argument against the inevitability of X, and then analyzed for how committed the author is to claiming X is bad and overturning X. Another interesting example is Hacking's description of essentialism as simply a way of talking about inevitability.
This book is somewhat disappointing if you're looking for simple answers to each of the questions posed, "is X socially constructed or not ?" However, it provides an extremely helpful way of looking at each case and trying to decide whether a 'social construction' critique actually has any value, or whether it just gives the history of the topic. Perhaps most useful is Hacking's "3 sticking points" with which to address the construction of a concept: contingency, nominalism, and stability.
This is a thinking person's book, but not nearly as incomprehensible to the layman as most works of modern philosophy, and much easier to read and more helpful than most of the "social construction" literature itself.
I'd go as far as to say that in many cases, we could replace the "social construction of X" arguments with Hacking's style of analysis about inevitability and the 3 sticking points, and come up with a more enlightening answer about the reality of the X in question.
If there is any flaw that I found here it is that I didn't think there was enough detail provided on any one topic to resolve the questions asked, they are pretty much all examples, and more questions are raised than answered. That can get maddening when you are just getting interested in the topic.