Overlapping ovals in a Venn diagram style of each of the types of work: as imagined, as prescribed, as disclosed, and as done

The Varieties Of Human Work” by Steven Shorrock (Safety Differently)

Early ergonomists realised that the analysis of work could not be limited to work as prescribed in procedures etc (le travail prescrit), nor to the observation of work actually done (le travail réalisé). Both have to be considered. But these are not the only varieties of work. Four basic varieties can be considered: work-as-imagined; work-as-prescribed; work-as-disclosed; and work-as-done. These are illustrated in the figure below, which shows that the varieties of human work do usually overlap, but not completely, leaving areas of commonality, and areas of difference. Here we will consider each variety, one by one.