This chapter serves as a short lead up on naturalism. One important variety of scientific naturalism is externalist. Noncognitivism was, in any case, one of the leading views and many of those who dissented from it still thought that naturalism about moral properties had been rendered implausible by the Open Question Argument. The chapter gives a brief overview of influential arguments against morals/motives and morals/reasons internalism. Philippa Foots' related arguments against internalism were taken up by the later naturalists, including the Cornell Realists who constructed metaethical theories inspired by science and skeptical of subjectivism. David Brink's chief argument in favor of externalism, works by positing a figure who he calls the amoralist who is stipulated to be someone who sincerely assents to a moral judgement to the effect that some act-type is morally required. It is an argument against two varieties of the morals/motives judgement internalism.