  By way of illustration, Russell (1999) recounts a baseball match from 1887 between Louisville and Brooklyn in which a Louisville player, Reddy Mack, who had just crossed home plate interfered with a Brooklyn catcher, preventing him from tagging another Louisville runner. While the interference was ongoing, another Louisville player crossed home plate. Crucially, at the time of the game, the rules prohibited only base runners from interfering with fielders. However, when Mack interfered with the Brooklyn fielder, he was no longer a runner, because he had crossed the home plate. So, the rules did not explicitly prohibit Mack from interfering with the fielder. If the umpire followed the rules strictly, then Mack’s interference should have been allowed, and the runner who followed Mack to home plate should not have been ruled out. However, as Russell notes, following the rules in this way would have invited further interference of fielders by non-base runners, so the game would likely have descended into a ‘nine-inning-long wrestling match’ (Russell, 1999: 28). To prevent such an outcome, the umpire read into existence a rule that prohibited non-base runners from interfering with fielders. So, he called out the runner who made it to home plate following Mack. This exercise of discretion was not subsequently overturned, and it precipitated a rule change to prohibit non-base runners from interfering with fielders. Indeed, it seemed necessary to depart from the rules to protect the nature of the sport. The umpire might be understood to have considered the purpose of the sport in deciding how he should rule on this incident. Baseball is a sport that tests excellence in running, batting, throwing and catching – but not wrestling. The umpire interpreted (and amended) the rules in light of the sport’s underlying purpose. In short, the umpire had to appeal to principles that underlie the rules and conventions to decide how the rules should be applied, and, in this case, to read a rule into existence. In inventing a rule to govern this situation which the rulemakers had likely never countenanced, the umpire protected the integrity of the game. For broad internalists, this example demonstrates the necessity of appeal to principles that precede the rules and conventions. 