’Ought’ Implies ‘Can’ and the Principle of Alternate Possibilities

In his paper \u27What we are morally responsible for\u27, Harry Frankfurt claims, in passing, that while the \u27Frankfurt Counterexamples\u27 are counterexamples to the Principle of Alternate Possibilities, they are not counterexamples to th famous Kantian maxim that \u27Ought\u27 implies \u27Can\u27. In an Analysis Paper of a few years ago, David Widerker objected to Frankfurt\u27s claim by arguing that the \u27Ought\u27 implies \u27Can\u27 maxim entails PAP; hence, counterexamples to PAP are counterexamples to the maxim as well