 In response some realists have defended ‘selective realism’ which concedes that while the majority of theories from the history of science have proven false, some of them have components that were retained in subsequent theories—these tend to be the components that were responsible for novel successes. Putative examples of this phenomenon are the caloric theory of heat and nineteenth century optical theories (Psillos 1999: Ch. 6), both of which were ultimately rejected as false but which had components that were retained in subsequent theories; these were the portions that were responsible for their novel  confirmations.[19]  So in line with the ultimate argument the claim is made that novel successes constitute a serious argument for the truth of the theory component which generates them. However, antirealists have responded by citing cases of theoretical claims that were subsequently determined to be entirely false but which managed nonetheless to generate impressive records of novel predictions. These include certain key claims made by Johannes Kepler in his Mysterium Cosmographicum (1596), assumptions used by Adams and Leverrier in the prediction of the planet Neptune’s existence and location (Lyons 2006), and Ptolemaic astronomy (Carman &amp; Díez 2015). Leconte (2017) maintains that predictive success legitimates only sceptical realism – the claim that some part of a theory is true, but it is not known which part. 