Dissertations, Theses, and Capstone Projects

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Steven M. Cahn


Stefan B. Baumrin

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Does evolution inform the ancient debate about the roles that instinct (emotion/passion/sentiment/feeling) and reason do and/or should play in how we decide what to do? Evolutionary ethicists typically adopt Darwinism as a suitable explanation for evolution, and on that basis draw conclusions about moral epistemology. However, if Darwinism is to be offered as a premise from which conclusions about moral epistemology are drawn, in order to assess such arguments we must assess that premise. This reveals the highly speculative and metaphysical quality of our theoretical explanations for how evolution happens. Clarifying that helps to facilitate an assessment of the epistemological claims of evolutionary ethicists. There are four general ways that instinct and reason can function in moral deliberation: descriptive instinctivism asserts that moral deliberation is necessarily a matter of instincts because control of the instincts by our faculty of reason is regarded (descriptively) as impossible; descriptive rationalism asserts that moral deliberation is necessarily a matter of reasoning, which (descriptively) must control instinct; prescriptive instinctivism asserts that moral deliberation can involve both rationality and instinct but prescribes following our instincts; prescriptive rationalism also asserts that deliberation can be either instinctive or rational but prescribes following reason. Micheal Ruse (2012), Peter Singer (2011), and Philip Kitcher (2011) each adopt Darwinism and on that basis arrive at descriptive instinctivism, descriptive rationalism, and prescriptive instinctivism, respectively. Our current level of understanding about evolution implies that prescriptive rationalism is a more practical approach to ethical deliberation than the other three alternatives described. Evolution can inform moral epistemology, but only very generally by helping to inform us of what we can justifiably believe about ourselves and nature.

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