Edited sentence: " In the Objectivist argument, it is simply assumed that the purpose of ethics is to preserve one's status as a human being (in the Objectivist sense), but many people predicate their ethical thinking on other premises, and Objectivism makes only very vague attempts to explain why they are wrong, if they are.But, as Nozick points out, this argument would need significant additional material to be logically sound.For instance, Rand claims that the concept of life is "metaphysically prior" to the concept of value, and so values must aim at preserving life.Pain is prior to the concept of pain relief, but that does not entail that the aim of pain relief should be to preserve pain.Thus, many mainstream philosophers hold that most of the substantive content of Objectivist ethics is merely asserted in its premises, and that it does not deduce its controversial conclusions from premises acceptable to most philosophers