“De Maximis Non Curat Lex” or how Context Reduces Science to Art in the Practice of Human Factors

Abstract

Frequently claims are made that what the discipline of human factors and ergonomics needs are better and more detailed data bases which can be used by designers as “look up” tables to specify the properties of human beings. Several of these already exist but they seem not to be satisfactory. The experience of teaching user centered design has convinced the author that the problem lies not in the absence of appropriate data tables for designers, but in the nature of the systems we design. Unlike many other engineering disciplines human factors is extremely sensitive to context. The result is that there are no such things as context free laws in applied psychology, and hence the value of data bases and tables is restricted to certain fairly basic ergonomic problems. It is moreover not merely in small details that laws do not apply - hence the title of this paper. Increasingly the nature of advanced systems renders such data bases of little value unless we can develop equivalent data bases which describe context, not merely the properties of humans.