 Many differences cannot be explained away in this fashion, however (FE 19). There are differences as to the ‘comparative worth of different goods’ (FE 19) and as to the stringency of the responsibilities Ross endorses (FE 186–188). These disagreements should not, he thinks, undermine our confidence that there is objective moral truth. But it is very hard to see a resolution to these problems. He says despite changes in scientific theories there is a sense science progresses toward the truth. The same is true in ethics. There is no reason to ‘doubt that man progresses fairly steadily towards moral truth as he does towards scientific’ (FE 20). The difficulty with this response is whereas in scientific matters there is an independent way of establishing progress, there is no such independent or seemingly independent way of establishing this in ethics. Recent research in the social sciences on moral judgement should not leave us confident (Greene 2008; Singer 2005).