Thos who focus on differences often tend to look more closely at boundaries than at the core of the phenomenon, whether it is social, biological or conceptual. So I was pleased to read this comment by Will Thomas regarding boundaries in social and historical contexts:
However, I want to finish with the provocative suggestion that, despite their porousness, boundaries are not, in general, very interesting places, mainly because they are intellectually impoverished. They are filled with superficial and often cliched polemics and items of exchange that only gain meaning when understood in the context of the more complex ideas lurking deep within particular territories. Until the main contours of these various territories are better mapped, these deeper meanings will remain opaque. Studies of life at the boundaries are more apt to rehearse what we know about the chaos and contingency of boundaries, and what we imagine we already know about life within the surrounding territories, than they are to reveal something genuinely new.
In biology, attempts to define the edges of taxa, ecosystems, organisms and historical groups of other kinds usually fails, because biological systems are not discrete, they are permeable and dynamic. What is called “essentialism”, which tries to identify such systems in terms of their innate and necessary properties, fails to do so for that reason. I have suggested before that it is better to focus on the mode or centre of these systems, and let the demarcation fall where it may. Thomas’ gives me a justification for this, in sociocultural history as well as biological history. Borders are impoverished. Sing it loud.