Critical digital systems and the ethic of expediency

Software based digital equipment is finding its way into critical applications. This paper suggests that in our quest to use this equipment, we must place this new technology in the perspective of past technologies. Our current practices and understanding of how to create error-free, failure-free, and hazard-free software are based on empirical observations. As users, our understanding of how to evaluate the systems we utilize is also based on empirical experience. Until we are able to create hazard-free software repeatably, we must, as a society, critically evaluate our uses of this technology.