Kant’s Groundwork is the most read and surely the most exasperating of his works on practical philosophy. Both its structure and its arguments remain obscure and controversial. A quick list of unsettled questions reminds one how much is in doubt. The list might include the following: Why does Kant shift the framework of his discussion three times in a short work? Does he establish that there is a supreme principle of morality? Does he show that the Categorical Imperative is that (...) supreme principle? Does he show that human beings are free agents for whom such principles of morality are important? What is the relationship between the various apparently distinct formulations of the Categorical Imperative? To what extent are any of them action-guiding? (shrink)

Philippa Foot; V—Moral Beliefs, Proceedings of the Aristotelian Society, Volume 59, Issue 1, 1 June 1959, Pages 83–104, https://doi.org/10.1093/aristotelian/59.