The difficulties of applying social science knowledge are founded in the difference between the functions of HRM knowledge and of social science knowledge. The main objective of the social sciences is not to assist managers to achieve their goals, or to sustain managerial legitimacy. Sociologists and psychologists are engaged in disciplines of enquiry, seeking knowledge for its own sake, to find causes and to establish patterns of evidence. Although social scientists may be recruited to assist managers, they remain uneasy bedfellows, tending to ask awkward questions, such as 'who benefits?' from actions, and also 'who says who benefits?' Far from offering single prescriptions, social scientists offer many different interpretations, based on varying and sometimes opposing paradigms (Kamoche, 1991). A survey in the UK of those at senior levels in HR whose origins were equally divided between line management (224 respondents) and those who had always specialised in HR (190 respondents) showed that strategic HRM was most important, and that HRM theories were regarded as least important by both groups of respondents (Tyson and Viney, 1996). It would seem, the pragmatic aspects of management and the significance of the organisational context negate some of the theoretical approaches from the practitioner's perspective.
There are, of course, basic techniques and knowledge areas in HRM which are portable across organisations, but such knowledge is not static, nor can it be applied without regard to organisational context. While these areas may include HR specialist knowledge, such as job evaluation, and more complex areas such as employment law, even these are subject to change and reflect the values of particular epochs. Computerbased job evaluation and the need for flexibility, avoiding bureaucracy and unresponsiveness, have changed how we describe and measure jobs, for example, (Pritchard and Murlis,1992). Employment law is changed by successive tribunal and court interpretations, to reflect current thinking as exemplified by recent judgments for example, in Waltons and Morse v Dorrington (1997) IRLR 488, the case about smoking. As one lawyer wrote of other cases concerning restrictive covenants: