To govern a problem such as ‘urban safety’, we first need to visualise it and name it. And any act of visualisation employs a particular scale – whether or not the scale is consciously chosen out of a set, or whether one simply takes up a certain scale without considering alternatives. A crucial insight of recent work on space and governance is that scale-effects pervade all visualisation, not just cartography and other two-dimensional representations. Standing on a mountain top to look down at one's town, for instance, one is using a different scale than that employed in – or as some scholars would put it, constituted by – walking down one's street. Scale is thus a fundamental feature or component of all efforts to render the world in thought.

In empirical social science, particularly in survey-based research, the terms ‘scale’ and ‘scaling’ are by no means absent. When researchers ponder whether they should assign numbers to the multiple-choice answers to a question or whether it is best to use qualitative terms such as ‘occasionally’ and ‘frequently’, they say they are thinking about ‘scaling’. Scaling in this sense is an issue that requires thought because even when questions have been written in such a way as to discourage ambiguity and creativity among respondents, anything more complicated than a yes-or-no answer requires paying attention to the implications of how responses are ‘scaled’.