Brian Leiter

Nietzsche holds that people lack freedom of the will in any sense that would be sufficient for ascriptions of moral responsibility; that the conscious experience we have of willing is actually epiphenomenal with respect to the actions that follow that experience; and that our actions largely arise through non-conscious processes (psychological and physiological) of which we are only dimly aware, and over which we exercise little or no conscious control. At the same time, Nietzsche, always a master of rhetoric, engages in a “persuasive definition” (Stevenson 1938) of the language of “freedom” and “free will,” to associate the positive valence of these terms with a certain Nietzschean ideal of the person unrelated to traditional notions of free will.

Evolutionary biology – or, more precisely, two (purported) applications of Darwin's theory of evolution by natural selection, namely, evolutionary psychology and what has been called human behavioral biology – is on the cusp of becoming the new rage among legal scholars looking for interdisciplinary insights into the law. We argue that as the actual science stands today, evolutionary biology offers nothing to help with questions about legal regulation of behavior. Only systematic misrepresentations or lack of understanding of the relevant biology, together with far-reaching analytical and philosophical confusions, have led anyone to think otherwise. Evolutionary accounts are etiological accounts of how a trait evolved. We argue that an account of causal etiology could be relevant to law if (1) the account of causal etiology is scientifically well-confirmed, and (2) there is an explanation of how the well-confirmed etiology bears on questions of development (what we call the Environmental Gap Objection). We then show that the accounts of causal etiology that might be relevant are not remotely well-confirmed by scientific standards. We argue, in particular, that (a) evolutionary psychology is not entitled to assume selectionist accounts of human behaviors, (b) the assumptions necessary for the selectionist accounts to be true are not warranted by standard criteria for theory choice, and (c) only confusions about levels of explanation of human behavior create the appearance that understanding the biology of behavior is important. We also note that no response to the Environmental Gap Objection has been proffered. In the concluding section of the article, we turn directly to the work of Owen Jones, a leading proponent of the relevance of evolutionary biology to law, and show that he does not come to terms with any of the fundamental problems identified in this article

General jurisprudence-that branch of legal philosophy concerned with the nature of law and adjudication-has been relatively unaffected by the "naturalistic" strains so evident, for example, in the epistemology, philosophy of mind and moral philosophy of the past forty years. This paper sketches three ways in which naturalism might affect jurisprudential inquiry. The paper serves as a kind of precis of the main themes in my book NATURALIZING JURISPRUDENCE: ESSAYS ON AMERICAN LEGAL REALISM AND NATURALISM IN LEGAL PHILOSOPHY (Oxford University Press, 2007).