Science, theory and technological knowledge abstract from particular contexts and their contingencies so as to provide general or universal knowledge and technical control. When we abstract, we isolate particular aspects of some object or situation, usually ones which are detachable in the sense of capable of existing in much the same form in different contexts, and hence generalizable or universal. We do this in everyday thought when we isolate particular aspects or qualities of more complex objects, for example when we call someone a consumer or taxpayer, or identify ‘reliability’ as a desirable trait. Abstraction can also be a physical process, as in the isolation of chemicals from an aggregate, or the separation of some specialised activity from the welter of activities that people otherwise engage in: thus, the division of labour involves a kind of material abstraction of particular kinds of tasks from others. In markets, when buyers and sellers meet, each tends to abstract from matters such as the welfare of those who made the goods, or the personal lives of traders, in order to focus on the business in hand. These latter examples show that abstractions are not necessarily arcane or obscure; ordinary language and practice are full of abstractions. (Sayer 2011: 67).

– Andrew Sayer