Disciplines within the field of computer science are addressing ethical problems through the lens of design justice, machine bias and fairness. These approaches have been key in fueling a relevant discussion about the social impact of technology within these fields. At the same time, they reduce justice, bias and fairness to mathematical issues and misconceive ethics as a discipline -leaving many aspects out of consideration. The lecture will illustrate with concrete cases why these approaches to ethics are too narrow to offer the adequate frame to address moral conflicts within technology.