and mind are opposites". Rand's ethics and politics are the most criticized areas of her philosophy. Several authors, including Robert Nozick and William F. O'Neill in two of the earliest academic critiques of her ideas, said she failed in her attempt to solve the is–ought problem. Critics have called her definitions of egoism and altruism biased and inconsistent with normal usage. Critics from religious traditions oppose her atheism and her rejection of altruism. Rand's political philosophy emphasized individual rights, including property rights. She considered laissez-faire capitalism the only moral social system because in her view it was the only system based on protecting those rights. Rand opposed collectivism and statism, which she considered to include many specific forms of government, such as communism, fascism, socialism, theocracy, and the welfare state. Her preferred form of government was a constitutional republic that is limited to the protection of individual rights. Although her political views are often classified as conservative or libertarian, Rand preferred the term "radical for capitalism". She worked with conservatives on political projects, but disagreed with them over issues such as religion and ethics. Rand denounced libertarianism, which she associated with anarchism. She rejected anarchism as a naive theory based in subjectivism that would lead to collectivism in practice. Several critics, including Nozick, have said her attempt to justify individual rights based on egoism fails. Others, like libertarian philosopher Michael Huemer, have gone further, saying that her support of egoism and her support of individual rights are inconsistent positions. Some critics, like Roy Childs, have said that her opposition to the initiation of force should lead to support of anarchism, rather than limited government. Relationship to other philosophers Except for Aristotle, Thomas Aquinas and classical liberals, Rand was sharply critical of most philosophers and philosophical traditions known to her. Acknowledging Aristotle as her greatest influence, Rand remarked that in the history of philosophy she could only recommend "three A's"—Aristotle, Aquinas, and Ayn Rand. In a 1959 interview with Mike Wallace, when asked where her philosophy came from, she responded: "Out of my own mind, with the sole acknowledgement of a debt to Aristotle, the only philosopher who ever influenced me." In an article for the Claremont Review of Books, political scientist Charles Murray criticized Rand's claim that her only "philosophical debt" was to Aristotle. He asserted her ideas were derivative of previous thinkers such as John Locke and Friedrich Nietzsche.